diff --git a/sys/contrib/openzfs/cmd/zdb/zdb.c b/sys/contrib/openzfs/cmd/zdb/zdb.c
index 2caa83f5c636..609e2c707b4b 100644
--- a/sys/contrib/openzfs/cmd/zdb/zdb.c
+++ b/sys/contrib/openzfs/cmd/zdb/zdb.c
@@ -1,9601 +1,9601 @@
 /*
  * CDDL HEADER START
  *
  * The contents of this file are subject to the terms of the
  * Common Development and Distribution License (the "License").
  * You may not use this file except in compliance with the License.
  *
  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  * or https://opensource.org/licenses/CDDL-1.0.
  * See the License for the specific language governing permissions
  * and limitations under the License.
  *
  * When distributing Covered Code, include this CDDL HEADER in each
  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  * If applicable, add the following below this CDDL HEADER, with the
  * fields enclosed by brackets "[]" replaced with your own identifying
  * information: Portions Copyright [yyyy] [name of copyright owner]
  *
  * CDDL HEADER END
  */
 
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2011, 2019 by Delphix. All rights reserved.
  * Copyright (c) 2014 Integros [integros.com]
  * Copyright 2016 Nexenta Systems, Inc.
  * Copyright (c) 2017, 2018 Lawrence Livermore National Security, LLC.
  * Copyright (c) 2015, 2017, Intel Corporation.
  * Copyright (c) 2020 Datto Inc.
  * Copyright (c) 2020, The FreeBSD Foundation [1]
  *
  * [1] Portions of this software were developed by Allan Jude
  *     under sponsorship from the FreeBSD Foundation.
  * Copyright (c) 2021 Allan Jude
  * Copyright (c) 2021 Toomas Soome <tsoome@me.com>
  * Copyright (c) 2023, Klara Inc.
  * Copyright (c) 2023, Rob Norris <robn@despairlabs.com>
  */
 
 #include <stdio.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <ctype.h>
 #include <getopt.h>
 #include <openssl/evp.h>
 #include <sys/zfs_context.h>
 #include <sys/spa.h>
 #include <sys/spa_impl.h>
 #include <sys/dmu.h>
 #include <sys/zap.h>
 #include <sys/zap_impl.h>
 #include <sys/fs/zfs.h>
 #include <sys/zfs_znode.h>
 #include <sys/zfs_sa.h>
 #include <sys/sa.h>
 #include <sys/sa_impl.h>
 #include <sys/vdev.h>
 #include <sys/vdev_impl.h>
 #include <sys/metaslab_impl.h>
 #include <sys/dmu_objset.h>
 #include <sys/dsl_dir.h>
 #include <sys/dsl_dataset.h>
 #include <sys/dsl_pool.h>
 #include <sys/dsl_bookmark.h>
 #include <sys/dbuf.h>
 #include <sys/zil.h>
 #include <sys/zil_impl.h>
 #include <sys/stat.h>
 #include <sys/resource.h>
 #include <sys/dmu_send.h>
 #include <sys/dmu_traverse.h>
 #include <sys/zio_checksum.h>
 #include <sys/zio_compress.h>
 #include <sys/zfs_fuid.h>
 #include <sys/arc.h>
 #include <sys/arc_impl.h>
 #include <sys/ddt.h>
 #include <sys/zfeature.h>
 #include <sys/abd.h>
 #include <sys/blkptr.h>
 #include <sys/dsl_crypt.h>
 #include <sys/dsl_scan.h>
 #include <sys/btree.h>
 #include <sys/brt.h>
 #include <sys/brt_impl.h>
 #include <zfs_comutil.h>
 #include <sys/zstd/zstd.h>
 #if (__GLIBC__ && !__UCLIBC__)
 #include <execinfo.h> /* for backtrace() */
 #endif
 
 #include <libnvpair.h>
 #include <libzutil.h>
 
 #include "zdb.h"
 
 #define	ZDB_COMPRESS_NAME(idx) ((idx) < ZIO_COMPRESS_FUNCTIONS ?	\
 	zio_compress_table[(idx)].ci_name : "UNKNOWN")
 #define	ZDB_CHECKSUM_NAME(idx) ((idx) < ZIO_CHECKSUM_FUNCTIONS ?	\
 	zio_checksum_table[(idx)].ci_name : "UNKNOWN")
 #define	ZDB_OT_TYPE(idx) ((idx) < DMU_OT_NUMTYPES ? (idx) :		\
 	(idx) == DMU_OTN_ZAP_DATA || (idx) == DMU_OTN_ZAP_METADATA ?	\
 	DMU_OT_ZAP_OTHER : \
 	(idx) == DMU_OTN_UINT64_DATA || (idx) == DMU_OTN_UINT64_METADATA ? \
 	DMU_OT_UINT64_OTHER : DMU_OT_NUMTYPES)
 
 /* Some platforms require part of inode IDs to be remapped */
 #ifdef __APPLE__
 #define	ZDB_MAP_OBJECT_ID(obj) INO_XNUTOZFS(obj, 2)
 #else
 #define	ZDB_MAP_OBJECT_ID(obj) (obj)
 #endif
 
 static const char *
 zdb_ot_name(dmu_object_type_t type)
 {
 	if (type < DMU_OT_NUMTYPES)
 		return (dmu_ot[type].ot_name);
 	else if ((type & DMU_OT_NEWTYPE) &&
 	    ((type & DMU_OT_BYTESWAP_MASK) < DMU_BSWAP_NUMFUNCS))
 		return (dmu_ot_byteswap[type & DMU_OT_BYTESWAP_MASK].ob_name);
 	else
 		return ("UNKNOWN");
 }
 
 extern int reference_tracking_enable;
 extern int zfs_recover;
 extern uint_t zfs_vdev_async_read_max_active;
 extern boolean_t spa_load_verify_dryrun;
 extern boolean_t spa_mode_readable_spacemaps;
 extern uint_t zfs_reconstruct_indirect_combinations_max;
 extern uint_t zfs_btree_verify_intensity;
 
 static const char cmdname[] = "zdb";
 uint8_t dump_opt[256];
 
 typedef void object_viewer_t(objset_t *, uint64_t, void *data, size_t size);
 
 static uint64_t *zopt_metaslab = NULL;
 static unsigned zopt_metaslab_args = 0;
 
 typedef struct zopt_object_range {
 	uint64_t zor_obj_start;
 	uint64_t zor_obj_end;
 	uint64_t zor_flags;
 } zopt_object_range_t;
 
 static zopt_object_range_t *zopt_object_ranges = NULL;
 static unsigned zopt_object_args = 0;
 
 static int flagbits[256];
 
 #define	ZOR_FLAG_PLAIN_FILE	0x0001
 #define	ZOR_FLAG_DIRECTORY	0x0002
 #define	ZOR_FLAG_SPACE_MAP	0x0004
 #define	ZOR_FLAG_ZAP		0x0008
 #define	ZOR_FLAG_ALL_TYPES	-1
 #define	ZOR_SUPPORTED_FLAGS	(ZOR_FLAG_PLAIN_FILE	| \
 				ZOR_FLAG_DIRECTORY	| \
 				ZOR_FLAG_SPACE_MAP	| \
 				ZOR_FLAG_ZAP)
 
 #define	ZDB_FLAG_CHECKSUM	0x0001
 #define	ZDB_FLAG_DECOMPRESS	0x0002
 #define	ZDB_FLAG_BSWAP		0x0004
 #define	ZDB_FLAG_GBH		0x0008
 #define	ZDB_FLAG_INDIRECT	0x0010
 #define	ZDB_FLAG_RAW		0x0020
 #define	ZDB_FLAG_PRINT_BLKPTR	0x0040
 #define	ZDB_FLAG_VERBOSE	0x0080
 
 static uint64_t max_inflight_bytes = 256 * 1024 * 1024; /* 256MB */
 static int leaked_objects = 0;
 static range_tree_t *mos_refd_objs;
 
 static void snprintf_blkptr_compact(char *, size_t, const blkptr_t *,
     boolean_t);
 static void mos_obj_refd(uint64_t);
 static void mos_obj_refd_multiple(uint64_t);
 static int dump_bpobj_cb(void *arg, const blkptr_t *bp, boolean_t free,
     dmu_tx_t *tx);
 
 typedef struct sublivelist_verify {
 	/* FREE's that haven't yet matched to an ALLOC, in one sub-livelist */
 	zfs_btree_t sv_pair;
 
 	/* ALLOC's without a matching FREE, accumulates across sub-livelists */
 	zfs_btree_t sv_leftover;
 } sublivelist_verify_t;
 
 static int
 livelist_compare(const void *larg, const void *rarg)
 {
 	const blkptr_t *l = larg;
 	const blkptr_t *r = rarg;
 
 	/* Sort them according to dva[0] */
 	uint64_t l_dva0_vdev, r_dva0_vdev;
 	l_dva0_vdev = DVA_GET_VDEV(&l->blk_dva[0]);
 	r_dva0_vdev = DVA_GET_VDEV(&r->blk_dva[0]);
 	if (l_dva0_vdev < r_dva0_vdev)
 		return (-1);
 	else if (l_dva0_vdev > r_dva0_vdev)
 		return (+1);
 
 	/* if vdevs are equal, sort by offsets. */
 	uint64_t l_dva0_offset;
 	uint64_t r_dva0_offset;
 	l_dva0_offset = DVA_GET_OFFSET(&l->blk_dva[0]);
 	r_dva0_offset = DVA_GET_OFFSET(&r->blk_dva[0]);
 	if (l_dva0_offset < r_dva0_offset) {
 		return (-1);
 	} else if (l_dva0_offset > r_dva0_offset) {
 		return (+1);
 	}
 
 	/*
 	 * Since we're storing blkptrs without cancelling FREE/ALLOC pairs,
 	 * it's possible the offsets are equal. In that case, sort by txg
 	 */
 	if (l->blk_birth < r->blk_birth) {
 		return (-1);
 	} else if (l->blk_birth > r->blk_birth) {
 		return (+1);
 	}
 	return (0);
 }
 
 typedef struct sublivelist_verify_block {
 	dva_t svb_dva;
 
 	/*
 	 * We need this to check if the block marked as allocated
 	 * in the livelist was freed (and potentially reallocated)
 	 * in the metaslab spacemaps at a later TXG.
 	 */
 	uint64_t svb_allocated_txg;
 } sublivelist_verify_block_t;
 
 static void zdb_print_blkptr(const blkptr_t *bp, int flags);
 
 typedef struct sublivelist_verify_block_refcnt {
 	/* block pointer entry in livelist being verified */
 	blkptr_t svbr_blk;
 
 	/*
 	 * Refcount gets incremented to 1 when we encounter the first
 	 * FREE entry for the svfbr block pointer and a node for it
 	 * is created in our ZDB verification/tracking metadata.
 	 *
 	 * As we encounter more FREE entries we increment this counter
 	 * and similarly decrement it whenever we find the respective
 	 * ALLOC entries for this block.
 	 *
 	 * When the refcount gets to 0 it means that all the FREE and
 	 * ALLOC entries of this block have paired up and we no longer
 	 * need to track it in our verification logic (e.g. the node
 	 * containing this struct in our verification data structure
 	 * should be freed).
 	 *
 	 * [refer to sublivelist_verify_blkptr() for the actual code]
 	 */
 	uint32_t svbr_refcnt;
 } sublivelist_verify_block_refcnt_t;
 
 static int
 sublivelist_block_refcnt_compare(const void *larg, const void *rarg)
 {
 	const sublivelist_verify_block_refcnt_t *l = larg;
 	const sublivelist_verify_block_refcnt_t *r = rarg;
 	return (livelist_compare(&l->svbr_blk, &r->svbr_blk));
 }
 
 static int
 sublivelist_verify_blkptr(void *arg, const blkptr_t *bp, boolean_t free,
     dmu_tx_t *tx)
 {
 	ASSERT3P(tx, ==, NULL);
 	struct sublivelist_verify *sv = arg;
 	sublivelist_verify_block_refcnt_t current = {
 			.svbr_blk = *bp,
 
 			/*
 			 * Start with 1 in case this is the first free entry.
 			 * This field is not used for our B-Tree comparisons
 			 * anyway.
 			 */
 			.svbr_refcnt = 1,
 	};
 
 	zfs_btree_index_t where;
 	sublivelist_verify_block_refcnt_t *pair =
 	    zfs_btree_find(&sv->sv_pair, &current, &where);
 	if (free) {
 		if (pair == NULL) {
 			/* first free entry for this block pointer */
 			zfs_btree_add(&sv->sv_pair, &current);
 		} else {
 			pair->svbr_refcnt++;
 		}
 	} else {
 		if (pair == NULL) {
 			/* block that is currently marked as allocated */
 			for (int i = 0; i < SPA_DVAS_PER_BP; i++) {
 				if (DVA_IS_EMPTY(&bp->blk_dva[i]))
 					break;
 				sublivelist_verify_block_t svb = {
 				    .svb_dva = bp->blk_dva[i],
 				    .svb_allocated_txg = bp->blk_birth
 				};
 
 				if (zfs_btree_find(&sv->sv_leftover, &svb,
 				    &where) == NULL) {
 					zfs_btree_add_idx(&sv->sv_leftover,
 					    &svb, &where);
 				}
 			}
 		} else {
 			/* alloc matches a free entry */
 			pair->svbr_refcnt--;
 			if (pair->svbr_refcnt == 0) {
 				/* all allocs and frees have been matched */
 				zfs_btree_remove_idx(&sv->sv_pair, &where);
 			}
 		}
 	}
 
 	return (0);
 }
 
 static int
 sublivelist_verify_func(void *args, dsl_deadlist_entry_t *dle)
 {
 	int err;
 	struct sublivelist_verify *sv = args;
 
 	zfs_btree_create(&sv->sv_pair, sublivelist_block_refcnt_compare, NULL,
 	    sizeof (sublivelist_verify_block_refcnt_t));
 
 	err = bpobj_iterate_nofree(&dle->dle_bpobj, sublivelist_verify_blkptr,
 	    sv, NULL);
 
 	sublivelist_verify_block_refcnt_t *e;
 	zfs_btree_index_t *cookie = NULL;
 	while ((e = zfs_btree_destroy_nodes(&sv->sv_pair, &cookie)) != NULL) {
 		char blkbuf[BP_SPRINTF_LEN];
 		snprintf_blkptr_compact(blkbuf, sizeof (blkbuf),
 		    &e->svbr_blk, B_TRUE);
 		(void) printf("\tERROR: %d unmatched FREE(s): %s\n",
 		    e->svbr_refcnt, blkbuf);
 	}
 	zfs_btree_destroy(&sv->sv_pair);
 
 	return (err);
 }
 
 static int
 livelist_block_compare(const void *larg, const void *rarg)
 {
 	const sublivelist_verify_block_t *l = larg;
 	const sublivelist_verify_block_t *r = rarg;
 
 	if (DVA_GET_VDEV(&l->svb_dva) < DVA_GET_VDEV(&r->svb_dva))
 		return (-1);
 	else if (DVA_GET_VDEV(&l->svb_dva) > DVA_GET_VDEV(&r->svb_dva))
 		return (+1);
 
 	if (DVA_GET_OFFSET(&l->svb_dva) < DVA_GET_OFFSET(&r->svb_dva))
 		return (-1);
 	else if (DVA_GET_OFFSET(&l->svb_dva) > DVA_GET_OFFSET(&r->svb_dva))
 		return (+1);
 
 	if (DVA_GET_ASIZE(&l->svb_dva) < DVA_GET_ASIZE(&r->svb_dva))
 		return (-1);
 	else if (DVA_GET_ASIZE(&l->svb_dva) > DVA_GET_ASIZE(&r->svb_dva))
 		return (+1);
 
 	return (0);
 }
 
 /*
  * Check for errors in a livelist while tracking all unfreed ALLOCs in the
  * sublivelist_verify_t: sv->sv_leftover
  */
 static void
 livelist_verify(dsl_deadlist_t *dl, void *arg)
 {
 	sublivelist_verify_t *sv = arg;
 	dsl_deadlist_iterate(dl, sublivelist_verify_func, sv);
 }
 
 /*
  * Check for errors in the livelist entry and discard the intermediary
  * data structures
  */
 static int
 sublivelist_verify_lightweight(void *args, dsl_deadlist_entry_t *dle)
 {
 	(void) args;
 	sublivelist_verify_t sv;
 	zfs_btree_create(&sv.sv_leftover, livelist_block_compare, NULL,
 	    sizeof (sublivelist_verify_block_t));
 	int err = sublivelist_verify_func(&sv, dle);
 	zfs_btree_clear(&sv.sv_leftover);
 	zfs_btree_destroy(&sv.sv_leftover);
 	return (err);
 }
 
 typedef struct metaslab_verify {
 	/*
 	 * Tree containing all the leftover ALLOCs from the livelists
 	 * that are part of this metaslab.
 	 */
 	zfs_btree_t mv_livelist_allocs;
 
 	/*
 	 * Metaslab information.
 	 */
 	uint64_t mv_vdid;
 	uint64_t mv_msid;
 	uint64_t mv_start;
 	uint64_t mv_end;
 
 	/*
 	 * What's currently allocated for this metaslab.
 	 */
 	range_tree_t *mv_allocated;
 } metaslab_verify_t;
 
 typedef void ll_iter_t(dsl_deadlist_t *ll, void *arg);
 
 typedef int (*zdb_log_sm_cb_t)(spa_t *spa, space_map_entry_t *sme, uint64_t txg,
     void *arg);
 
 typedef struct unflushed_iter_cb_arg {
 	spa_t *uic_spa;
 	uint64_t uic_txg;
 	void *uic_arg;
 	zdb_log_sm_cb_t uic_cb;
 } unflushed_iter_cb_arg_t;
 
 static int
 iterate_through_spacemap_logs_cb(space_map_entry_t *sme, void *arg)
 {
 	unflushed_iter_cb_arg_t *uic = arg;
 	return (uic->uic_cb(uic->uic_spa, sme, uic->uic_txg, uic->uic_arg));
 }
 
 static void
 iterate_through_spacemap_logs(spa_t *spa, zdb_log_sm_cb_t cb, void *arg)
 {
 	if (!spa_feature_is_active(spa, SPA_FEATURE_LOG_SPACEMAP))
 		return;
 
 	spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
 	for (spa_log_sm_t *sls = avl_first(&spa->spa_sm_logs_by_txg);
 	    sls; sls = AVL_NEXT(&spa->spa_sm_logs_by_txg, sls)) {
 		space_map_t *sm = NULL;
 		VERIFY0(space_map_open(&sm, spa_meta_objset(spa),
 		    sls->sls_sm_obj, 0, UINT64_MAX, SPA_MINBLOCKSHIFT));
 
 		unflushed_iter_cb_arg_t uic = {
 			.uic_spa = spa,
 			.uic_txg = sls->sls_txg,
 			.uic_arg = arg,
 			.uic_cb = cb
 		};
 		VERIFY0(space_map_iterate(sm, space_map_length(sm),
 		    iterate_through_spacemap_logs_cb, &uic));
 		space_map_close(sm);
 	}
 	spa_config_exit(spa, SCL_CONFIG, FTAG);
 }
 
 static void
 verify_livelist_allocs(metaslab_verify_t *mv, uint64_t txg,
     uint64_t offset, uint64_t size)
 {
 	sublivelist_verify_block_t svb = {{{0}}};
 	DVA_SET_VDEV(&svb.svb_dva, mv->mv_vdid);
 	DVA_SET_OFFSET(&svb.svb_dva, offset);
 	DVA_SET_ASIZE(&svb.svb_dva, size);
 	zfs_btree_index_t where;
 	uint64_t end_offset = offset + size;
 
 	/*
 	 *  Look for an exact match for spacemap entry in the livelist entries.
 	 *  Then, look for other livelist entries that fall within the range
 	 *  of the spacemap entry as it may have been condensed
 	 */
 	sublivelist_verify_block_t *found =
 	    zfs_btree_find(&mv->mv_livelist_allocs, &svb, &where);
 	if (found == NULL) {
 		found = zfs_btree_next(&mv->mv_livelist_allocs, &where, &where);
 	}
 	for (; found != NULL && DVA_GET_VDEV(&found->svb_dva) == mv->mv_vdid &&
 	    DVA_GET_OFFSET(&found->svb_dva) < end_offset;
 	    found = zfs_btree_next(&mv->mv_livelist_allocs, &where, &where)) {
 		if (found->svb_allocated_txg <= txg) {
 			(void) printf("ERROR: Livelist ALLOC [%llx:%llx] "
 			    "from TXG %llx FREED at TXG %llx\n",
 			    (u_longlong_t)DVA_GET_OFFSET(&found->svb_dva),
 			    (u_longlong_t)DVA_GET_ASIZE(&found->svb_dva),
 			    (u_longlong_t)found->svb_allocated_txg,
 			    (u_longlong_t)txg);
 		}
 	}
 }
 
 static int
 metaslab_spacemap_validation_cb(space_map_entry_t *sme, void *arg)
 {
 	metaslab_verify_t *mv = arg;
 	uint64_t offset = sme->sme_offset;
 	uint64_t size = sme->sme_run;
 	uint64_t txg = sme->sme_txg;
 
 	if (sme->sme_type == SM_ALLOC) {
 		if (range_tree_contains(mv->mv_allocated,
 		    offset, size)) {
 			(void) printf("ERROR: DOUBLE ALLOC: "
 			    "%llu [%llx:%llx] "
 			    "%llu:%llu LOG_SM\n",
 			    (u_longlong_t)txg, (u_longlong_t)offset,
 			    (u_longlong_t)size, (u_longlong_t)mv->mv_vdid,
 			    (u_longlong_t)mv->mv_msid);
 		} else {
 			range_tree_add(mv->mv_allocated,
 			    offset, size);
 		}
 	} else {
 		if (!range_tree_contains(mv->mv_allocated,
 		    offset, size)) {
 			(void) printf("ERROR: DOUBLE FREE: "
 			    "%llu [%llx:%llx] "
 			    "%llu:%llu LOG_SM\n",
 			    (u_longlong_t)txg, (u_longlong_t)offset,
 			    (u_longlong_t)size, (u_longlong_t)mv->mv_vdid,
 			    (u_longlong_t)mv->mv_msid);
 		} else {
 			range_tree_remove(mv->mv_allocated,
 			    offset, size);
 		}
 	}
 
 	if (sme->sme_type != SM_ALLOC) {
 		/*
 		 * If something is freed in the spacemap, verify that
 		 * it is not listed as allocated in the livelist.
 		 */
 		verify_livelist_allocs(mv, txg, offset, size);
 	}
 	return (0);
 }
 
 static int
 spacemap_check_sm_log_cb(spa_t *spa, space_map_entry_t *sme,
     uint64_t txg, void *arg)
 {
 	metaslab_verify_t *mv = arg;
 	uint64_t offset = sme->sme_offset;
 	uint64_t vdev_id = sme->sme_vdev;
 
 	vdev_t *vd = vdev_lookup_top(spa, vdev_id);
 
 	/* skip indirect vdevs */
 	if (!vdev_is_concrete(vd))
 		return (0);
 
 	if (vdev_id != mv->mv_vdid)
 		return (0);
 
 	metaslab_t *ms = vd->vdev_ms[offset >> vd->vdev_ms_shift];
 	if (ms->ms_id != mv->mv_msid)
 		return (0);
 
 	if (txg < metaslab_unflushed_txg(ms))
 		return (0);
 
 
 	ASSERT3U(txg, ==, sme->sme_txg);
 	return (metaslab_spacemap_validation_cb(sme, mv));
 }
 
 static void
 spacemap_check_sm_log(spa_t *spa, metaslab_verify_t *mv)
 {
 	iterate_through_spacemap_logs(spa, spacemap_check_sm_log_cb, mv);
 }
 
 static void
 spacemap_check_ms_sm(space_map_t  *sm, metaslab_verify_t *mv)
 {
 	if (sm == NULL)
 		return;
 
 	VERIFY0(space_map_iterate(sm, space_map_length(sm),
 	    metaslab_spacemap_validation_cb, mv));
 }
 
 static void iterate_deleted_livelists(spa_t *spa, ll_iter_t func, void *arg);
 
 /*
  * Transfer blocks from sv_leftover tree to the mv_livelist_allocs if
  * they are part of that metaslab (mv_msid).
  */
 static void
 mv_populate_livelist_allocs(metaslab_verify_t *mv, sublivelist_verify_t *sv)
 {
 	zfs_btree_index_t where;
 	sublivelist_verify_block_t *svb;
 	ASSERT3U(zfs_btree_numnodes(&mv->mv_livelist_allocs), ==, 0);
 	for (svb = zfs_btree_first(&sv->sv_leftover, &where);
 	    svb != NULL;
 	    svb = zfs_btree_next(&sv->sv_leftover, &where, &where)) {
 		if (DVA_GET_VDEV(&svb->svb_dva) != mv->mv_vdid)
 			continue;
 
 		if (DVA_GET_OFFSET(&svb->svb_dva) < mv->mv_start &&
 		    (DVA_GET_OFFSET(&svb->svb_dva) +
 		    DVA_GET_ASIZE(&svb->svb_dva)) > mv->mv_start) {
 			(void) printf("ERROR: Found block that crosses "
 			    "metaslab boundary: <%llu:%llx:%llx>\n",
 			    (u_longlong_t)DVA_GET_VDEV(&svb->svb_dva),
 			    (u_longlong_t)DVA_GET_OFFSET(&svb->svb_dva),
 			    (u_longlong_t)DVA_GET_ASIZE(&svb->svb_dva));
 			continue;
 		}
 
 		if (DVA_GET_OFFSET(&svb->svb_dva) < mv->mv_start)
 			continue;
 
 		if (DVA_GET_OFFSET(&svb->svb_dva) >= mv->mv_end)
 			continue;
 
 		if ((DVA_GET_OFFSET(&svb->svb_dva) +
 		    DVA_GET_ASIZE(&svb->svb_dva)) > mv->mv_end) {
 			(void) printf("ERROR: Found block that crosses "
 			    "metaslab boundary: <%llu:%llx:%llx>\n",
 			    (u_longlong_t)DVA_GET_VDEV(&svb->svb_dva),
 			    (u_longlong_t)DVA_GET_OFFSET(&svb->svb_dva),
 			    (u_longlong_t)DVA_GET_ASIZE(&svb->svb_dva));
 			continue;
 		}
 
 		zfs_btree_add(&mv->mv_livelist_allocs, svb);
 	}
 
 	for (svb = zfs_btree_first(&mv->mv_livelist_allocs, &where);
 	    svb != NULL;
 	    svb = zfs_btree_next(&mv->mv_livelist_allocs, &where, &where)) {
 		zfs_btree_remove(&sv->sv_leftover, svb);
 	}
 }
 
 /*
  * [Livelist Check]
  * Iterate through all the sublivelists and:
  * - report leftover frees (**)
  * - record leftover ALLOCs together with their TXG [see Cross Check]
  *
  * (**) Note: Double ALLOCs are valid in datasets that have dedup
  *      enabled. Similarly double FREEs are allowed as well but
  *      only if they pair up with a corresponding ALLOC entry once
  *      we our done with our sublivelist iteration.
  *
  * [Spacemap Check]
  * for each metaslab:
  * - iterate over spacemap and then the metaslab's entries in the
  *   spacemap log, then report any double FREEs and ALLOCs (do not
  *   blow up).
  *
  * [Cross Check]
  * After finishing the Livelist Check phase and while being in the
  * Spacemap Check phase, we find all the recorded leftover ALLOCs
  * of the livelist check that are part of the metaslab that we are
  * currently looking at in the Spacemap Check. We report any entries
  * that are marked as ALLOCs in the livelists but have been actually
  * freed (and potentially allocated again) after their TXG stamp in
  * the spacemaps. Also report any ALLOCs from the livelists that
  * belong to indirect vdevs (e.g. their vdev completed removal).
  *
  * Note that this will miss Log Spacemap entries that cancelled each other
  * out before being flushed to the metaslab, so we are not guaranteed
  * to match all erroneous ALLOCs.
  */
 static void
 livelist_metaslab_validate(spa_t *spa)
 {
 	(void) printf("Verifying deleted livelist entries\n");
 
 	sublivelist_verify_t sv;
 	zfs_btree_create(&sv.sv_leftover, livelist_block_compare, NULL,
 	    sizeof (sublivelist_verify_block_t));
 	iterate_deleted_livelists(spa, livelist_verify, &sv);
 
 	(void) printf("Verifying metaslab entries\n");
 	vdev_t *rvd = spa->spa_root_vdev;
 	for (uint64_t c = 0; c < rvd->vdev_children; c++) {
 		vdev_t *vd = rvd->vdev_child[c];
 
 		if (!vdev_is_concrete(vd))
 			continue;
 
 		for (uint64_t mid = 0; mid < vd->vdev_ms_count; mid++) {
 			metaslab_t *m = vd->vdev_ms[mid];
 
 			(void) fprintf(stderr,
 			    "\rverifying concrete vdev %llu, "
 			    "metaslab %llu of %llu ...",
 			    (longlong_t)vd->vdev_id,
 			    (longlong_t)mid,
 			    (longlong_t)vd->vdev_ms_count);
 
 			uint64_t shift, start;
 			range_seg_type_t type =
 			    metaslab_calculate_range_tree_type(vd, m,
 			    &start, &shift);
 			metaslab_verify_t mv;
 			mv.mv_allocated = range_tree_create(NULL,
 			    type, NULL, start, shift);
 			mv.mv_vdid = vd->vdev_id;
 			mv.mv_msid = m->ms_id;
 			mv.mv_start = m->ms_start;
 			mv.mv_end = m->ms_start + m->ms_size;
 			zfs_btree_create(&mv.mv_livelist_allocs,
 			    livelist_block_compare, NULL,
 			    sizeof (sublivelist_verify_block_t));
 
 			mv_populate_livelist_allocs(&mv, &sv);
 
 			spacemap_check_ms_sm(m->ms_sm, &mv);
 			spacemap_check_sm_log(spa, &mv);
 
 			range_tree_vacate(mv.mv_allocated, NULL, NULL);
 			range_tree_destroy(mv.mv_allocated);
 			zfs_btree_clear(&mv.mv_livelist_allocs);
 			zfs_btree_destroy(&mv.mv_livelist_allocs);
 		}
 	}
 	(void) fprintf(stderr, "\n");
 
 	/*
 	 * If there are any segments in the leftover tree after we walked
 	 * through all the metaslabs in the concrete vdevs then this means
 	 * that we have segments in the livelists that belong to indirect
 	 * vdevs and are marked as allocated.
 	 */
 	if (zfs_btree_numnodes(&sv.sv_leftover) == 0) {
 		zfs_btree_destroy(&sv.sv_leftover);
 		return;
 	}
 	(void) printf("ERROR: Found livelist blocks marked as allocated "
 	    "for indirect vdevs:\n");
 
 	zfs_btree_index_t *where = NULL;
 	sublivelist_verify_block_t *svb;
 	while ((svb = zfs_btree_destroy_nodes(&sv.sv_leftover, &where)) !=
 	    NULL) {
 		int vdev_id = DVA_GET_VDEV(&svb->svb_dva);
 		ASSERT3U(vdev_id, <, rvd->vdev_children);
 		vdev_t *vd = rvd->vdev_child[vdev_id];
 		ASSERT(!vdev_is_concrete(vd));
 		(void) printf("<%d:%llx:%llx> TXG %llx\n",
 		    vdev_id, (u_longlong_t)DVA_GET_OFFSET(&svb->svb_dva),
 		    (u_longlong_t)DVA_GET_ASIZE(&svb->svb_dva),
 		    (u_longlong_t)svb->svb_allocated_txg);
 	}
 	(void) printf("\n");
 	zfs_btree_destroy(&sv.sv_leftover);
 }
 
 /*
  * These libumem hooks provide a reasonable set of defaults for the allocator's
  * debugging facilities.
  */
 const char *
 _umem_debug_init(void)
 {
 	return ("default,verbose"); /* $UMEM_DEBUG setting */
 }
 
 const char *
 _umem_logging_init(void)
 {
 	return ("fail,contents"); /* $UMEM_LOGGING setting */
 }
 
 static void
 usage(void)
 {
 	(void) fprintf(stderr,
 	    "Usage:\t%s [-AbcdDFGhikLMPsvXy] [-e [-V] [-p <path> ...]] "
 	    "[-I <inflight I/Os>]\n"
 	    "\t\t[-o <var>=<value>]... [-t <txg>] [-U <cache>] [-x <dumpdir>]\n"
 	    "\t\t[-K <key>]\n"
 	    "\t\t[<poolname>[/<dataset | objset id>] [<object | range> ...]]\n"
 	    "\t%s [-AdiPv] [-e [-V] [-p <path> ...]] [-U <cache>] [-K <key>]\n"
 	    "\t\t[<poolname>[/<dataset | objset id>] [<object | range> ...]\n"
 	    "\t%s -B [-e [-V] [-p <path> ...]] [-I <inflight I/Os>]\n"
 	    "\t\t[-o <var>=<value>]... [-t <txg>] [-U <cache>] [-x <dumpdir>]\n"
 	    "\t\t[-K <key>] <poolname>/<objset id> [<backupflags>]\n"
 	    "\t%s [-v] <bookmark>\n"
 	    "\t%s -C [-A] [-U <cache>] [<poolname>]\n"
 	    "\t%s -l [-Aqu] <device>\n"
 	    "\t%s -m [-AFLPX] [-e [-V] [-p <path> ...]] [-t <txg>] "
 	    "[-U <cache>]\n\t\t<poolname> [<vdev> [<metaslab> ...]]\n"
 	    "\t%s -O [-K <key>] <dataset> <path>\n"
 	    "\t%s -r [-K <key>] <dataset> <path> <destination>\n"
 	    "\t%s -R [-A] [-e [-V] [-p <path> ...]] [-U <cache>]\n"
 	    "\t\t<poolname> <vdev>:<offset>:<size>[:<flags>]\n"
 	    "\t%s -E [-A] word0:word1:...:word15\n"
 	    "\t%s -S [-AP] [-e [-V] [-p <path> ...]] [-U <cache>] "
 	    "<poolname>\n\n",
 	    cmdname, cmdname, cmdname, cmdname, cmdname, cmdname, cmdname,
 	    cmdname, cmdname, cmdname, cmdname, cmdname);
 
 	(void) fprintf(stderr, "    Dataset name must include at least one "
 	    "separator character '/' or '@'\n");
 	(void) fprintf(stderr, "    If dataset name is specified, only that "
 	    "dataset is dumped\n");
 	(void) fprintf(stderr,  "    If object numbers or object number "
 	    "ranges are specified, only those\n"
 	    "    objects or ranges are dumped.\n\n");
 	(void) fprintf(stderr,
 	    "    Object ranges take the form <start>:<end>[:<flags>]\n"
 	    "        start    Starting object number\n"
 	    "        end      Ending object number, or -1 for no upper bound\n"
 	    "        flags    Optional flags to select object types:\n"
 	    "            A     All objects (this is the default)\n"
 	    "            d     ZFS directories\n"
 	    "            f     ZFS files \n"
 	    "            m     SPA space maps\n"
 	    "            z     ZAPs\n"
 	    "            -     Negate effect of next flag\n\n");
 	(void) fprintf(stderr, "    Options to control amount of output:\n");
 	(void) fprintf(stderr, "        -b --block-stats             "
 	    "block statistics\n");
 	(void) fprintf(stderr, "        -B --backup                  "
 	    "backup stream\n");
 	(void) fprintf(stderr, "        -c --checksum                "
 	    "checksum all metadata (twice for all data) blocks\n");
 	(void) fprintf(stderr, "        -C --config                  "
 	    "config (or cachefile if alone)\n");
 	(void) fprintf(stderr, "        -d --datasets                "
 	    "dataset(s)\n");
 	(void) fprintf(stderr, "        -D --dedup-stats             "
 	    "dedup statistics\n");
 	(void) fprintf(stderr, "        -E --embedded-block-pointer=INTEGER\n"
 	    "                                     decode and display block "
 	    "from an embedded block pointer\n");
 	(void) fprintf(stderr, "        -h --history                 "
 	    "pool history\n");
 	(void) fprintf(stderr, "        -i --intent-logs             "
 	    "intent logs\n");
 	(void) fprintf(stderr, "        -l --label                   "
 	    "read label contents\n");
 	(void) fprintf(stderr, "        -k --checkpointed-state      "
 	    "examine the checkpointed state of the pool\n");
 	(void) fprintf(stderr, "        -L --disable-leak-tracking   "
 	    "disable leak tracking (do not load spacemaps)\n");
 	(void) fprintf(stderr, "        -m --metaslabs               "
 	    "metaslabs\n");
 	(void) fprintf(stderr, "        -M --metaslab-groups         "
 	    "metaslab groups\n");
 	(void) fprintf(stderr, "        -O --object-lookups          "
 	    "perform object lookups by path\n");
 	(void) fprintf(stderr, "        -r --copy-object             "
 	    "copy an object by path to file\n");
 	(void) fprintf(stderr, "        -R --read-block              "
 	    "read and display block from a device\n");
 	(void) fprintf(stderr, "        -s --io-stats                "
 	    "report stats on zdb's I/O\n");
 	(void) fprintf(stderr, "        -S --simulate-dedup          "
 	    "simulate dedup to measure effect\n");
 	(void) fprintf(stderr, "        -v --verbose                 "
 	    "verbose (applies to all others)\n");
 	(void) fprintf(stderr, "        -y --livelist                "
 	    "perform livelist and metaslab validation on any livelists being "
 	    "deleted\n\n");
 	(void) fprintf(stderr, "    Below options are intended for use "
 	    "with other options:\n");
 	(void) fprintf(stderr, "        -A --ignore-assertions       "
 	    "ignore assertions (-A), enable panic recovery (-AA) or both "
 	    "(-AAA)\n");
 	(void) fprintf(stderr, "        -e --exported                "
 	    "pool is exported/destroyed/has altroot/not in a cachefile\n");
 	(void) fprintf(stderr, "        -F --automatic-rewind        "
 	    "attempt automatic rewind within safe range of transaction "
 	    "groups\n");
 	(void) fprintf(stderr, "        -G --dump-debug-msg          "
 	    "dump zfs_dbgmsg buffer before exiting\n");
 	(void) fprintf(stderr, "        -I --inflight=INTEGER        "
 	    "specify the maximum number of checksumming I/Os "
 	    "[default is 200]\n");
 	(void) fprintf(stderr, "        -K --key=KEY                 "
 	    "decryption key for encrypted dataset\n");
 	(void) fprintf(stderr, "        -o --option=\"OPTION=INTEGER\" "
 	    "set global variable to an unsigned 32-bit integer\n");
 	(void) fprintf(stderr, "        -p --path==PATH              "
 	    "use one or more with -e to specify path to vdev dir\n");
 	(void) fprintf(stderr, "        -P --parseable               "
 	    "print numbers in parseable form\n");
 	(void) fprintf(stderr, "        -q --skip-label              "
 	    "don't print label contents\n");
 	(void) fprintf(stderr, "        -t --txg=INTEGER             "
 	    "highest txg to use when searching for uberblocks\n");
 	(void) fprintf(stderr, "        -T --brt-stats               "
 	    "BRT statistics\n");
 	(void) fprintf(stderr, "        -u --uberblock               "
 	    "uberblock\n");
 	(void) fprintf(stderr, "        -U --cachefile=PATH          "
 	    "use alternate cachefile\n");
 	(void) fprintf(stderr, "        -V --verbatim                "
 	    "do verbatim import\n");
 	(void) fprintf(stderr, "        -x --dump-blocks=PATH        "
 	    "dump all read blocks into specified directory\n");
 	(void) fprintf(stderr, "        -X --extreme-rewind          "
 	    "attempt extreme rewind (does not work with dataset)\n");
 	(void) fprintf(stderr, "        -Y --all-reconstruction      "
 	    "attempt all reconstruction combinations for split blocks\n");
 	(void) fprintf(stderr, "        -Z --zstd-headers            "
 	    "show ZSTD headers \n");
 	(void) fprintf(stderr, "Specify an option more than once (e.g. -bb) "
 	    "to make only that option verbose\n");
 	(void) fprintf(stderr, "Default is to dump everything non-verbosely\n");
 	exit(1);
 }
 
 static void
 dump_debug_buffer(void)
 {
 	ssize_t ret __attribute__((unused));
 
 	if (!dump_opt['G'])
 		return;
 	/*
 	 * We use write() instead of printf() so that this function
 	 * is safe to call from a signal handler.
 	 */
 	ret = write(STDOUT_FILENO, "\n", 1);
 	zfs_dbgmsg_print("zdb");
 }
 
 #define	BACKTRACE_SZ	100
 
 static void sig_handler(int signo)
 {
 	struct sigaction action;
 #if (__GLIBC__ && !__UCLIBC__) /* backtrace() is a GNU extension */
 	int nptrs;
 	void *buffer[BACKTRACE_SZ];
 
 	nptrs = backtrace(buffer, BACKTRACE_SZ);
 	backtrace_symbols_fd(buffer, nptrs, STDERR_FILENO);
 #endif
 	dump_debug_buffer();
 
 	/*
 	 * Restore default action and re-raise signal so SIGSEGV and
 	 * SIGABRT can trigger a core dump.
 	 */
 	action.sa_handler = SIG_DFL;
 	sigemptyset(&action.sa_mask);
 	action.sa_flags = 0;
 	(void) sigaction(signo, &action, NULL);
 	raise(signo);
 }
 
 /*
  * Called for usage errors that are discovered after a call to spa_open(),
  * dmu_bonus_hold(), or pool_match().  abort() is called for other errors.
  */
 
 static void
 fatal(const char *fmt, ...)
 {
 	va_list ap;
 
 	va_start(ap, fmt);
 	(void) fprintf(stderr, "%s: ", cmdname);
 	(void) vfprintf(stderr, fmt, ap);
 	va_end(ap);
 	(void) fprintf(stderr, "\n");
 
 	dump_debug_buffer();
 
 	exit(1);
 }
 
 static void
 dump_packed_nvlist(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) size;
 	nvlist_t *nv;
 	size_t nvsize = *(uint64_t *)data;
 	char *packed = umem_alloc(nvsize, UMEM_NOFAIL);
 
 	VERIFY(0 == dmu_read(os, object, 0, nvsize, packed, DMU_READ_PREFETCH));
 
 	VERIFY(nvlist_unpack(packed, nvsize, &nv, 0) == 0);
 
 	umem_free(packed, nvsize);
 
 	dump_nvlist(nv, 8);
 
 	nvlist_free(nv);
 }
 
 static void
 dump_history_offsets(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) os, (void) object, (void) size;
 	spa_history_phys_t *shp = data;
 
 	if (shp == NULL)
 		return;
 
 	(void) printf("\t\tpool_create_len = %llu\n",
 	    (u_longlong_t)shp->sh_pool_create_len);
 	(void) printf("\t\tphys_max_off = %llu\n",
 	    (u_longlong_t)shp->sh_phys_max_off);
 	(void) printf("\t\tbof = %llu\n",
 	    (u_longlong_t)shp->sh_bof);
 	(void) printf("\t\teof = %llu\n",
 	    (u_longlong_t)shp->sh_eof);
 	(void) printf("\t\trecords_lost = %llu\n",
 	    (u_longlong_t)shp->sh_records_lost);
 }
 
 static void
 zdb_nicenum(uint64_t num, char *buf, size_t buflen)
 {
 	if (dump_opt['P'])
 		(void) snprintf(buf, buflen, "%llu", (longlong_t)num);
 	else
 		nicenum(num, buf, buflen);
 }
 
 static void
 zdb_nicebytes(uint64_t bytes, char *buf, size_t buflen)
 {
 	if (dump_opt['P'])
 		(void) snprintf(buf, buflen, "%llu", (longlong_t)bytes);
 	else
 		zfs_nicebytes(bytes, buf, buflen);
 }
 
 static const char histo_stars[] = "****************************************";
 static const uint64_t histo_width = sizeof (histo_stars) - 1;
 
 static void
 dump_histogram(const uint64_t *histo, int size, int offset)
 {
 	int i;
 	int minidx = size - 1;
 	int maxidx = 0;
 	uint64_t max = 0;
 
 	for (i = 0; i < size; i++) {
 		if (histo[i] == 0)
 			continue;
 		if (histo[i] > max)
 			max = histo[i];
 		if (i > maxidx)
 			maxidx = i;
 		if (i < minidx)
 			minidx = i;
 	}
 
 	if (max < histo_width)
 		max = histo_width;
 
 	for (i = minidx; i <= maxidx; i++) {
 		(void) printf("\t\t\t%3u: %6llu %s\n",
 		    i + offset, (u_longlong_t)histo[i],
 		    &histo_stars[(max - histo[i]) * histo_width / max]);
 	}
 }
 
 static void
 dump_zap_stats(objset_t *os, uint64_t object)
 {
 	int error;
 	zap_stats_t zs;
 
 	error = zap_get_stats(os, object, &zs);
 	if (error)
 		return;
 
 	if (zs.zs_ptrtbl_len == 0) {
 		ASSERT(zs.zs_num_blocks == 1);
 		(void) printf("\tmicrozap: %llu bytes, %llu entries\n",
 		    (u_longlong_t)zs.zs_blocksize,
 		    (u_longlong_t)zs.zs_num_entries);
 		return;
 	}
 
 	(void) printf("\tFat ZAP stats:\n");
 
 	(void) printf("\t\tPointer table:\n");
 	(void) printf("\t\t\t%llu elements\n",
 	    (u_longlong_t)zs.zs_ptrtbl_len);
 	(void) printf("\t\t\tzt_blk: %llu\n",
 	    (u_longlong_t)zs.zs_ptrtbl_zt_blk);
 	(void) printf("\t\t\tzt_numblks: %llu\n",
 	    (u_longlong_t)zs.zs_ptrtbl_zt_numblks);
 	(void) printf("\t\t\tzt_shift: %llu\n",
 	    (u_longlong_t)zs.zs_ptrtbl_zt_shift);
 	(void) printf("\t\t\tzt_blks_copied: %llu\n",
 	    (u_longlong_t)zs.zs_ptrtbl_blks_copied);
 	(void) printf("\t\t\tzt_nextblk: %llu\n",
 	    (u_longlong_t)zs.zs_ptrtbl_nextblk);
 
 	(void) printf("\t\tZAP entries: %llu\n",
 	    (u_longlong_t)zs.zs_num_entries);
 	(void) printf("\t\tLeaf blocks: %llu\n",
 	    (u_longlong_t)zs.zs_num_leafs);
 	(void) printf("\t\tTotal blocks: %llu\n",
 	    (u_longlong_t)zs.zs_num_blocks);
 	(void) printf("\t\tzap_block_type: 0x%llx\n",
 	    (u_longlong_t)zs.zs_block_type);
 	(void) printf("\t\tzap_magic: 0x%llx\n",
 	    (u_longlong_t)zs.zs_magic);
 	(void) printf("\t\tzap_salt: 0x%llx\n",
 	    (u_longlong_t)zs.zs_salt);
 
 	(void) printf("\t\tLeafs with 2^n pointers:\n");
 	dump_histogram(zs.zs_leafs_with_2n_pointers, ZAP_HISTOGRAM_SIZE, 0);
 
 	(void) printf("\t\tBlocks with n*5 entries:\n");
 	dump_histogram(zs.zs_blocks_with_n5_entries, ZAP_HISTOGRAM_SIZE, 0);
 
 	(void) printf("\t\tBlocks n/10 full:\n");
 	dump_histogram(zs.zs_blocks_n_tenths_full, ZAP_HISTOGRAM_SIZE, 0);
 
 	(void) printf("\t\tEntries with n chunks:\n");
 	dump_histogram(zs.zs_entries_using_n_chunks, ZAP_HISTOGRAM_SIZE, 0);
 
 	(void) printf("\t\tBuckets with n entries:\n");
 	dump_histogram(zs.zs_buckets_with_n_entries, ZAP_HISTOGRAM_SIZE, 0);
 }
 
 static void
 dump_none(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) os, (void) object, (void) data, (void) size;
 }
 
 static void
 dump_unknown(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) os, (void) object, (void) data, (void) size;
 	(void) printf("\tUNKNOWN OBJECT TYPE\n");
 }
 
 static void
 dump_uint8(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) os, (void) object, (void) data, (void) size;
 }
 
 static void
 dump_uint64(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	uint64_t *arr;
 	uint64_t oursize;
 	if (dump_opt['d'] < 6)
 		return;
 
 	if (data == NULL) {
 		dmu_object_info_t doi;
 
 		VERIFY0(dmu_object_info(os, object, &doi));
 		size = doi.doi_max_offset;
 		/*
 		 * We cap the size at 1 mebibyte here to prevent
 		 * allocation failures and nigh-infinite printing if the
 		 * object is extremely large.
 		 */
 		oursize = MIN(size, 1 << 20);
 		arr = kmem_alloc(oursize, KM_SLEEP);
 
 		int err = dmu_read(os, object, 0, oursize, arr, 0);
 		if (err != 0) {
 			(void) printf("got error %u from dmu_read\n", err);
 			kmem_free(arr, oursize);
 			return;
 		}
 	} else {
 		/*
 		 * Even though the allocation is already done in this code path,
 		 * we still cap the size to prevent excessive printing.
 		 */
 		oursize = MIN(size, 1 << 20);
 		arr = data;
 	}
 
 	if (size == 0) {
 		if (data == NULL)
 			kmem_free(arr, oursize);
 		(void) printf("\t\t[]\n");
 		return;
 	}
 
 	(void) printf("\t\t[%0llx", (u_longlong_t)arr[0]);
 	for (size_t i = 1; i * sizeof (uint64_t) < oursize; i++) {
 		if (i % 4 != 0)
 			(void) printf(", %0llx", (u_longlong_t)arr[i]);
 		else
 			(void) printf(",\n\t\t%0llx", (u_longlong_t)arr[i]);
 	}
 	if (oursize != size)
 		(void) printf(", ... ");
 	(void) printf("]\n");
 
 	if (data == NULL)
 		kmem_free(arr, oursize);
 }
 
 static void
 dump_zap(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) data, (void) size;
 	zap_cursor_t zc;
 	zap_attribute_t attr;
 	void *prop;
 	unsigned i;
 
 	dump_zap_stats(os, object);
 	(void) printf("\n");
 
 	for (zap_cursor_init(&zc, os, object);
 	    zap_cursor_retrieve(&zc, &attr) == 0;
 	    zap_cursor_advance(&zc)) {
 		boolean_t key64 =
 		    !!(zap_getflags(zc.zc_zap) & ZAP_FLAG_UINT64_KEY);
 
 		if (key64)
-			(void) printf("\t\t0x%010lx = ",
-			    *(uint64_t *)attr.za_name);
+			(void) printf("\t\t0x%010llx = ",
+			    (u_longlong_t)*(uint64_t *)attr.za_name);
 		else
 			(void) printf("\t\t%s = ", attr.za_name);
 
 		if (attr.za_num_integers == 0) {
 			(void) printf("\n");
 			continue;
 		}
 		prop = umem_zalloc(attr.za_num_integers *
 		    attr.za_integer_length, UMEM_NOFAIL);
 
 		if (key64)
 			(void) zap_lookup_uint64(os, object,
 			    (const uint64_t *)attr.za_name, 1,
 			    attr.za_integer_length, attr.za_num_integers,
 			    prop);
 		else
 			(void) zap_lookup(os, object, attr.za_name,
 			    attr.za_integer_length, attr.za_num_integers,
 			    prop);
 
 		if (attr.za_integer_length == 1 && !key64) {
 			if (strcmp(attr.za_name,
 			    DSL_CRYPTO_KEY_MASTER_KEY) == 0 ||
 			    strcmp(attr.za_name,
 			    DSL_CRYPTO_KEY_HMAC_KEY) == 0 ||
 			    strcmp(attr.za_name, DSL_CRYPTO_KEY_IV) == 0 ||
 			    strcmp(attr.za_name, DSL_CRYPTO_KEY_MAC) == 0 ||
 			    strcmp(attr.za_name, DMU_POOL_CHECKSUM_SALT) == 0) {
 				uint8_t *u8 = prop;
 
 				for (i = 0; i < attr.za_num_integers; i++) {
 					(void) printf("%02x", u8[i]);
 				}
 			} else {
 				(void) printf("%s", (char *)prop);
 			}
 		} else {
 			for (i = 0; i < attr.za_num_integers; i++) {
 				switch (attr.za_integer_length) {
 				case 1:
 					(void) printf("%u ",
 					    ((uint8_t *)prop)[i]);
 					break;
 				case 2:
 					(void) printf("%u ",
 					    ((uint16_t *)prop)[i]);
 					break;
 				case 4:
 					(void) printf("%u ",
 					    ((uint32_t *)prop)[i]);
 					break;
 				case 8:
 					(void) printf("%lld ",
 					    (u_longlong_t)((int64_t *)prop)[i]);
 					break;
 				}
 			}
 		}
 		(void) printf("\n");
 		umem_free(prop, attr.za_num_integers * attr.za_integer_length);
 	}
 	zap_cursor_fini(&zc);
 }
 
 static void
 dump_bpobj(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	bpobj_phys_t *bpop = data;
 	uint64_t i;
 	char bytes[32], comp[32], uncomp[32];
 
 	/* make sure the output won't get truncated */
 	_Static_assert(sizeof (bytes) >= NN_NUMBUF_SZ, "bytes truncated");
 	_Static_assert(sizeof (comp) >= NN_NUMBUF_SZ, "comp truncated");
 	_Static_assert(sizeof (uncomp) >= NN_NUMBUF_SZ, "uncomp truncated");
 
 	if (bpop == NULL)
 		return;
 
 	zdb_nicenum(bpop->bpo_bytes, bytes, sizeof (bytes));
 	zdb_nicenum(bpop->bpo_comp, comp, sizeof (comp));
 	zdb_nicenum(bpop->bpo_uncomp, uncomp, sizeof (uncomp));
 
 	(void) printf("\t\tnum_blkptrs = %llu\n",
 	    (u_longlong_t)bpop->bpo_num_blkptrs);
 	(void) printf("\t\tbytes = %s\n", bytes);
 	if (size >= BPOBJ_SIZE_V1) {
 		(void) printf("\t\tcomp = %s\n", comp);
 		(void) printf("\t\tuncomp = %s\n", uncomp);
 	}
 	if (size >= BPOBJ_SIZE_V2) {
 		(void) printf("\t\tsubobjs = %llu\n",
 		    (u_longlong_t)bpop->bpo_subobjs);
 		(void) printf("\t\tnum_subobjs = %llu\n",
 		    (u_longlong_t)bpop->bpo_num_subobjs);
 	}
 	if (size >= sizeof (*bpop)) {
 		(void) printf("\t\tnum_freed = %llu\n",
 		    (u_longlong_t)bpop->bpo_num_freed);
 	}
 
 	if (dump_opt['d'] < 5)
 		return;
 
 	for (i = 0; i < bpop->bpo_num_blkptrs; i++) {
 		char blkbuf[BP_SPRINTF_LEN];
 		blkptr_t bp;
 
 		int err = dmu_read(os, object,
 		    i * sizeof (bp), sizeof (bp), &bp, 0);
 		if (err != 0) {
 			(void) printf("got error %u from dmu_read\n", err);
 			break;
 		}
 		snprintf_blkptr_compact(blkbuf, sizeof (blkbuf), &bp,
 		    BP_GET_FREE(&bp));
 		(void) printf("\t%s\n", blkbuf);
 	}
 }
 
 static void
 dump_bpobj_subobjs(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) data, (void) size;
 	dmu_object_info_t doi;
 	int64_t i;
 
 	VERIFY0(dmu_object_info(os, object, &doi));
 	uint64_t *subobjs = kmem_alloc(doi.doi_max_offset, KM_SLEEP);
 
 	int err = dmu_read(os, object, 0, doi.doi_max_offset, subobjs, 0);
 	if (err != 0) {
 		(void) printf("got error %u from dmu_read\n", err);
 		kmem_free(subobjs, doi.doi_max_offset);
 		return;
 	}
 
 	int64_t last_nonzero = -1;
 	for (i = 0; i < doi.doi_max_offset / 8; i++) {
 		if (subobjs[i] != 0)
 			last_nonzero = i;
 	}
 
 	for (i = 0; i <= last_nonzero; i++) {
 		(void) printf("\t%llu\n", (u_longlong_t)subobjs[i]);
 	}
 	kmem_free(subobjs, doi.doi_max_offset);
 }
 
 static void
 dump_ddt_zap(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) data, (void) size;
 	dump_zap_stats(os, object);
 	/* contents are printed elsewhere, properly decoded */
 }
 
 static void
 dump_sa_attrs(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) data, (void) size;
 	zap_cursor_t zc;
 	zap_attribute_t attr;
 
 	dump_zap_stats(os, object);
 	(void) printf("\n");
 
 	for (zap_cursor_init(&zc, os, object);
 	    zap_cursor_retrieve(&zc, &attr) == 0;
 	    zap_cursor_advance(&zc)) {
 		(void) printf("\t\t%s = ", attr.za_name);
 		if (attr.za_num_integers == 0) {
 			(void) printf("\n");
 			continue;
 		}
 		(void) printf(" %llx : [%d:%d:%d]\n",
 		    (u_longlong_t)attr.za_first_integer,
 		    (int)ATTR_LENGTH(attr.za_first_integer),
 		    (int)ATTR_BSWAP(attr.za_first_integer),
 		    (int)ATTR_NUM(attr.za_first_integer));
 	}
 	zap_cursor_fini(&zc);
 }
 
 static void
 dump_sa_layouts(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) data, (void) size;
 	zap_cursor_t zc;
 	zap_attribute_t attr;
 	uint16_t *layout_attrs;
 	unsigned i;
 
 	dump_zap_stats(os, object);
 	(void) printf("\n");
 
 	for (zap_cursor_init(&zc, os, object);
 	    zap_cursor_retrieve(&zc, &attr) == 0;
 	    zap_cursor_advance(&zc)) {
 		(void) printf("\t\t%s = [", attr.za_name);
 		if (attr.za_num_integers == 0) {
 			(void) printf("\n");
 			continue;
 		}
 
 		VERIFY(attr.za_integer_length == 2);
 		layout_attrs = umem_zalloc(attr.za_num_integers *
 		    attr.za_integer_length, UMEM_NOFAIL);
 
 		VERIFY(zap_lookup(os, object, attr.za_name,
 		    attr.za_integer_length,
 		    attr.za_num_integers, layout_attrs) == 0);
 
 		for (i = 0; i != attr.za_num_integers; i++)
 			(void) printf(" %d ", (int)layout_attrs[i]);
 		(void) printf("]\n");
 		umem_free(layout_attrs,
 		    attr.za_num_integers * attr.za_integer_length);
 	}
 	zap_cursor_fini(&zc);
 }
 
 static void
 dump_zpldir(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) data, (void) size;
 	zap_cursor_t zc;
 	zap_attribute_t attr;
 	const char *typenames[] = {
 		/* 0 */ "not specified",
 		/* 1 */ "FIFO",
 		/* 2 */ "Character Device",
 		/* 3 */ "3 (invalid)",
 		/* 4 */ "Directory",
 		/* 5 */ "5 (invalid)",
 		/* 6 */ "Block Device",
 		/* 7 */ "7 (invalid)",
 		/* 8 */ "Regular File",
 		/* 9 */ "9 (invalid)",
 		/* 10 */ "Symbolic Link",
 		/* 11 */ "11 (invalid)",
 		/* 12 */ "Socket",
 		/* 13 */ "Door",
 		/* 14 */ "Event Port",
 		/* 15 */ "15 (invalid)",
 	};
 
 	dump_zap_stats(os, object);
 	(void) printf("\n");
 
 	for (zap_cursor_init(&zc, os, object);
 	    zap_cursor_retrieve(&zc, &attr) == 0;
 	    zap_cursor_advance(&zc)) {
 		(void) printf("\t\t%s = %lld (type: %s)\n",
 		    attr.za_name, ZFS_DIRENT_OBJ(attr.za_first_integer),
 		    typenames[ZFS_DIRENT_TYPE(attr.za_first_integer)]);
 	}
 	zap_cursor_fini(&zc);
 }
 
 static int
 get_dtl_refcount(vdev_t *vd)
 {
 	int refcount = 0;
 
 	if (vd->vdev_ops->vdev_op_leaf) {
 		space_map_t *sm = vd->vdev_dtl_sm;
 
 		if (sm != NULL &&
 		    sm->sm_dbuf->db_size == sizeof (space_map_phys_t))
 			return (1);
 		return (0);
 	}
 
 	for (unsigned c = 0; c < vd->vdev_children; c++)
 		refcount += get_dtl_refcount(vd->vdev_child[c]);
 	return (refcount);
 }
 
 static int
 get_metaslab_refcount(vdev_t *vd)
 {
 	int refcount = 0;
 
 	if (vd->vdev_top == vd) {
 		for (uint64_t m = 0; m < vd->vdev_ms_count; m++) {
 			space_map_t *sm = vd->vdev_ms[m]->ms_sm;
 
 			if (sm != NULL &&
 			    sm->sm_dbuf->db_size == sizeof (space_map_phys_t))
 				refcount++;
 		}
 	}
 	for (unsigned c = 0; c < vd->vdev_children; c++)
 		refcount += get_metaslab_refcount(vd->vdev_child[c]);
 
 	return (refcount);
 }
 
 static int
 get_obsolete_refcount(vdev_t *vd)
 {
 	uint64_t obsolete_sm_object;
 	int refcount = 0;
 
 	VERIFY0(vdev_obsolete_sm_object(vd, &obsolete_sm_object));
 	if (vd->vdev_top == vd && obsolete_sm_object != 0) {
 		dmu_object_info_t doi;
 		VERIFY0(dmu_object_info(vd->vdev_spa->spa_meta_objset,
 		    obsolete_sm_object, &doi));
 		if (doi.doi_bonus_size == sizeof (space_map_phys_t)) {
 			refcount++;
 		}
 	} else {
 		ASSERT3P(vd->vdev_obsolete_sm, ==, NULL);
 		ASSERT3U(obsolete_sm_object, ==, 0);
 	}
 	for (unsigned c = 0; c < vd->vdev_children; c++) {
 		refcount += get_obsolete_refcount(vd->vdev_child[c]);
 	}
 
 	return (refcount);
 }
 
 static int
 get_prev_obsolete_spacemap_refcount(spa_t *spa)
 {
 	uint64_t prev_obj =
 	    spa->spa_condensing_indirect_phys.scip_prev_obsolete_sm_object;
 	if (prev_obj != 0) {
 		dmu_object_info_t doi;
 		VERIFY0(dmu_object_info(spa->spa_meta_objset, prev_obj, &doi));
 		if (doi.doi_bonus_size == sizeof (space_map_phys_t)) {
 			return (1);
 		}
 	}
 	return (0);
 }
 
 static int
 get_checkpoint_refcount(vdev_t *vd)
 {
 	int refcount = 0;
 
 	if (vd->vdev_top == vd && vd->vdev_top_zap != 0 &&
 	    zap_contains(spa_meta_objset(vd->vdev_spa),
 	    vd->vdev_top_zap, VDEV_TOP_ZAP_POOL_CHECKPOINT_SM) == 0)
 		refcount++;
 
 	for (uint64_t c = 0; c < vd->vdev_children; c++)
 		refcount += get_checkpoint_refcount(vd->vdev_child[c]);
 
 	return (refcount);
 }
 
 static int
 get_log_spacemap_refcount(spa_t *spa)
 {
 	return (avl_numnodes(&spa->spa_sm_logs_by_txg));
 }
 
 static int
 verify_spacemap_refcounts(spa_t *spa)
 {
 	uint64_t expected_refcount = 0;
 	uint64_t actual_refcount;
 
 	(void) feature_get_refcount(spa,
 	    &spa_feature_table[SPA_FEATURE_SPACEMAP_HISTOGRAM],
 	    &expected_refcount);
 	actual_refcount = get_dtl_refcount(spa->spa_root_vdev);
 	actual_refcount += get_metaslab_refcount(spa->spa_root_vdev);
 	actual_refcount += get_obsolete_refcount(spa->spa_root_vdev);
 	actual_refcount += get_prev_obsolete_spacemap_refcount(spa);
 	actual_refcount += get_checkpoint_refcount(spa->spa_root_vdev);
 	actual_refcount += get_log_spacemap_refcount(spa);
 
 	if (expected_refcount != actual_refcount) {
 		(void) printf("space map refcount mismatch: expected %lld != "
 		    "actual %lld\n",
 		    (longlong_t)expected_refcount,
 		    (longlong_t)actual_refcount);
 		return (2);
 	}
 	return (0);
 }
 
 static void
 dump_spacemap(objset_t *os, space_map_t *sm)
 {
 	const char *ddata[] = { "ALLOC", "FREE", "CONDENSE", "INVALID",
 	    "INVALID", "INVALID", "INVALID", "INVALID" };
 
 	if (sm == NULL)
 		return;
 
 	(void) printf("space map object %llu:\n",
 	    (longlong_t)sm->sm_object);
 	(void) printf("  smp_length = 0x%llx\n",
 	    (longlong_t)sm->sm_phys->smp_length);
 	(void) printf("  smp_alloc = 0x%llx\n",
 	    (longlong_t)sm->sm_phys->smp_alloc);
 
 	if (dump_opt['d'] < 6 && dump_opt['m'] < 4)
 		return;
 
 	/*
 	 * Print out the freelist entries in both encoded and decoded form.
 	 */
 	uint8_t mapshift = sm->sm_shift;
 	int64_t alloc = 0;
 	uint64_t word, entry_id = 0;
 	for (uint64_t offset = 0; offset < space_map_length(sm);
 	    offset += sizeof (word)) {
 
 		VERIFY0(dmu_read(os, space_map_object(sm), offset,
 		    sizeof (word), &word, DMU_READ_PREFETCH));
 
 		if (sm_entry_is_debug(word)) {
 			uint64_t de_txg = SM_DEBUG_TXG_DECODE(word);
 			uint64_t de_sync_pass = SM_DEBUG_SYNCPASS_DECODE(word);
 			if (de_txg == 0) {
 				(void) printf(
 				    "\t    [%6llu] PADDING\n",
 				    (u_longlong_t)entry_id);
 			} else {
 				(void) printf(
 				    "\t    [%6llu] %s: txg %llu pass %llu\n",
 				    (u_longlong_t)entry_id,
 				    ddata[SM_DEBUG_ACTION_DECODE(word)],
 				    (u_longlong_t)de_txg,
 				    (u_longlong_t)de_sync_pass);
 			}
 			entry_id++;
 			continue;
 		}
 
 		uint8_t words;
 		char entry_type;
 		uint64_t entry_off, entry_run, entry_vdev = SM_NO_VDEVID;
 
 		if (sm_entry_is_single_word(word)) {
 			entry_type = (SM_TYPE_DECODE(word) == SM_ALLOC) ?
 			    'A' : 'F';
 			entry_off = (SM_OFFSET_DECODE(word) << mapshift) +
 			    sm->sm_start;
 			entry_run = SM_RUN_DECODE(word) << mapshift;
 			words = 1;
 		} else {
 			/* it is a two-word entry so we read another word */
 			ASSERT(sm_entry_is_double_word(word));
 
 			uint64_t extra_word;
 			offset += sizeof (extra_word);
 			VERIFY0(dmu_read(os, space_map_object(sm), offset,
 			    sizeof (extra_word), &extra_word,
 			    DMU_READ_PREFETCH));
 
 			ASSERT3U(offset, <=, space_map_length(sm));
 
 			entry_run = SM2_RUN_DECODE(word) << mapshift;
 			entry_vdev = SM2_VDEV_DECODE(word);
 			entry_type = (SM2_TYPE_DECODE(extra_word) == SM_ALLOC) ?
 			    'A' : 'F';
 			entry_off = (SM2_OFFSET_DECODE(extra_word) <<
 			    mapshift) + sm->sm_start;
 			words = 2;
 		}
 
 		(void) printf("\t    [%6llu]    %c  range:"
 		    " %010llx-%010llx  size: %06llx vdev: %06llu words: %u\n",
 		    (u_longlong_t)entry_id,
 		    entry_type, (u_longlong_t)entry_off,
 		    (u_longlong_t)(entry_off + entry_run),
 		    (u_longlong_t)entry_run,
 		    (u_longlong_t)entry_vdev, words);
 
 		if (entry_type == 'A')
 			alloc += entry_run;
 		else
 			alloc -= entry_run;
 		entry_id++;
 	}
 	if (alloc != space_map_allocated(sm)) {
 		(void) printf("space_map_object alloc (%lld) INCONSISTENT "
 		    "with space map summary (%lld)\n",
 		    (longlong_t)space_map_allocated(sm), (longlong_t)alloc);
 	}
 }
 
 static void
 dump_metaslab_stats(metaslab_t *msp)
 {
 	char maxbuf[32];
 	range_tree_t *rt = msp->ms_allocatable;
 	zfs_btree_t *t = &msp->ms_allocatable_by_size;
 	int free_pct = range_tree_space(rt) * 100 / msp->ms_size;
 
 	/* max sure nicenum has enough space */
 	_Static_assert(sizeof (maxbuf) >= NN_NUMBUF_SZ, "maxbuf truncated");
 
 	zdb_nicenum(metaslab_largest_allocatable(msp), maxbuf, sizeof (maxbuf));
 
 	(void) printf("\t %25s %10lu   %7s  %6s   %4s %4d%%\n",
 	    "segments", zfs_btree_numnodes(t), "maxsize", maxbuf,
 	    "freepct", free_pct);
 	(void) printf("\tIn-memory histogram:\n");
 	dump_histogram(rt->rt_histogram, RANGE_TREE_HISTOGRAM_SIZE, 0);
 }
 
 static void
 dump_metaslab(metaslab_t *msp)
 {
 	vdev_t *vd = msp->ms_group->mg_vd;
 	spa_t *spa = vd->vdev_spa;
 	space_map_t *sm = msp->ms_sm;
 	char freebuf[32];
 
 	zdb_nicenum(msp->ms_size - space_map_allocated(sm), freebuf,
 	    sizeof (freebuf));
 
 	(void) printf(
 	    "\tmetaslab %6llu   offset %12llx   spacemap %6llu   free    %5s\n",
 	    (u_longlong_t)msp->ms_id, (u_longlong_t)msp->ms_start,
 	    (u_longlong_t)space_map_object(sm), freebuf);
 
 	if (dump_opt['m'] > 2 && !dump_opt['L']) {
 		mutex_enter(&msp->ms_lock);
 		VERIFY0(metaslab_load(msp));
 		range_tree_stat_verify(msp->ms_allocatable);
 		dump_metaslab_stats(msp);
 		metaslab_unload(msp);
 		mutex_exit(&msp->ms_lock);
 	}
 
 	if (dump_opt['m'] > 1 && sm != NULL &&
 	    spa_feature_is_active(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM)) {
 		/*
 		 * The space map histogram represents free space in chunks
 		 * of sm_shift (i.e. bucket 0 refers to 2^sm_shift).
 		 */
 		(void) printf("\tOn-disk histogram:\t\tfragmentation %llu\n",
 		    (u_longlong_t)msp->ms_fragmentation);
 		dump_histogram(sm->sm_phys->smp_histogram,
 		    SPACE_MAP_HISTOGRAM_SIZE, sm->sm_shift);
 	}
 
 	if (vd->vdev_ops == &vdev_draid_ops)
 		ASSERT3U(msp->ms_size, <=, 1ULL << vd->vdev_ms_shift);
 	else
 		ASSERT3U(msp->ms_size, ==, 1ULL << vd->vdev_ms_shift);
 
 	dump_spacemap(spa->spa_meta_objset, msp->ms_sm);
 
 	if (spa_feature_is_active(spa, SPA_FEATURE_LOG_SPACEMAP)) {
 		(void) printf("\tFlush data:\n\tunflushed txg=%llu\n\n",
 		    (u_longlong_t)metaslab_unflushed_txg(msp));
 	}
 }
 
 static void
 print_vdev_metaslab_header(vdev_t *vd)
 {
 	vdev_alloc_bias_t alloc_bias = vd->vdev_alloc_bias;
 	const char *bias_str = "";
 	if (alloc_bias == VDEV_BIAS_LOG || vd->vdev_islog) {
 		bias_str = VDEV_ALLOC_BIAS_LOG;
 	} else if (alloc_bias == VDEV_BIAS_SPECIAL) {
 		bias_str = VDEV_ALLOC_BIAS_SPECIAL;
 	} else if (alloc_bias == VDEV_BIAS_DEDUP) {
 		bias_str = VDEV_ALLOC_BIAS_DEDUP;
 	}
 
 	uint64_t ms_flush_data_obj = 0;
 	if (vd->vdev_top_zap != 0) {
 		int error = zap_lookup(spa_meta_objset(vd->vdev_spa),
 		    vd->vdev_top_zap, VDEV_TOP_ZAP_MS_UNFLUSHED_PHYS_TXGS,
 		    sizeof (uint64_t), 1, &ms_flush_data_obj);
 		if (error != ENOENT) {
 			ASSERT0(error);
 		}
 	}
 
 	(void) printf("\tvdev %10llu   %s",
 	    (u_longlong_t)vd->vdev_id, bias_str);
 
 	if (ms_flush_data_obj != 0) {
 		(void) printf("   ms_unflushed_phys object %llu",
 		    (u_longlong_t)ms_flush_data_obj);
 	}
 
 	(void) printf("\n\t%-10s%5llu   %-19s   %-15s   %-12s\n",
 	    "metaslabs", (u_longlong_t)vd->vdev_ms_count,
 	    "offset", "spacemap", "free");
 	(void) printf("\t%15s   %19s   %15s   %12s\n",
 	    "---------------", "-------------------",
 	    "---------------", "------------");
 }
 
 static void
 dump_metaslab_groups(spa_t *spa, boolean_t show_special)
 {
 	vdev_t *rvd = spa->spa_root_vdev;
 	metaslab_class_t *mc = spa_normal_class(spa);
 	metaslab_class_t *smc = spa_special_class(spa);
 	uint64_t fragmentation;
 
 	metaslab_class_histogram_verify(mc);
 
 	for (unsigned c = 0; c < rvd->vdev_children; c++) {
 		vdev_t *tvd = rvd->vdev_child[c];
 		metaslab_group_t *mg = tvd->vdev_mg;
 
 		if (mg == NULL || (mg->mg_class != mc &&
 		    (!show_special || mg->mg_class != smc)))
 			continue;
 
 		metaslab_group_histogram_verify(mg);
 		mg->mg_fragmentation = metaslab_group_fragmentation(mg);
 
 		(void) printf("\tvdev %10llu\t\tmetaslabs%5llu\t\t"
 		    "fragmentation",
 		    (u_longlong_t)tvd->vdev_id,
 		    (u_longlong_t)tvd->vdev_ms_count);
 		if (mg->mg_fragmentation == ZFS_FRAG_INVALID) {
 			(void) printf("%3s\n", "-");
 		} else {
 			(void) printf("%3llu%%\n",
 			    (u_longlong_t)mg->mg_fragmentation);
 		}
 		dump_histogram(mg->mg_histogram, RANGE_TREE_HISTOGRAM_SIZE, 0);
 	}
 
 	(void) printf("\tpool %s\tfragmentation", spa_name(spa));
 	fragmentation = metaslab_class_fragmentation(mc);
 	if (fragmentation == ZFS_FRAG_INVALID)
 		(void) printf("\t%3s\n", "-");
 	else
 		(void) printf("\t%3llu%%\n", (u_longlong_t)fragmentation);
 	dump_histogram(mc->mc_histogram, RANGE_TREE_HISTOGRAM_SIZE, 0);
 }
 
 static void
 print_vdev_indirect(vdev_t *vd)
 {
 	vdev_indirect_config_t *vic = &vd->vdev_indirect_config;
 	vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping;
 	vdev_indirect_births_t *vib = vd->vdev_indirect_births;
 
 	if (vim == NULL) {
 		ASSERT3P(vib, ==, NULL);
 		return;
 	}
 
 	ASSERT3U(vdev_indirect_mapping_object(vim), ==,
 	    vic->vic_mapping_object);
 	ASSERT3U(vdev_indirect_births_object(vib), ==,
 	    vic->vic_births_object);
 
 	(void) printf("indirect births obj %llu:\n",
 	    (longlong_t)vic->vic_births_object);
 	(void) printf("    vib_count = %llu\n",
 	    (longlong_t)vdev_indirect_births_count(vib));
 	for (uint64_t i = 0; i < vdev_indirect_births_count(vib); i++) {
 		vdev_indirect_birth_entry_phys_t *cur_vibe =
 		    &vib->vib_entries[i];
 		(void) printf("\toffset %llx -> txg %llu\n",
 		    (longlong_t)cur_vibe->vibe_offset,
 		    (longlong_t)cur_vibe->vibe_phys_birth_txg);
 	}
 	(void) printf("\n");
 
 	(void) printf("indirect mapping obj %llu:\n",
 	    (longlong_t)vic->vic_mapping_object);
 	(void) printf("    vim_max_offset = 0x%llx\n",
 	    (longlong_t)vdev_indirect_mapping_max_offset(vim));
 	(void) printf("    vim_bytes_mapped = 0x%llx\n",
 	    (longlong_t)vdev_indirect_mapping_bytes_mapped(vim));
 	(void) printf("    vim_count = %llu\n",
 	    (longlong_t)vdev_indirect_mapping_num_entries(vim));
 
 	if (dump_opt['d'] <= 5 && dump_opt['m'] <= 3)
 		return;
 
 	uint32_t *counts = vdev_indirect_mapping_load_obsolete_counts(vim);
 
 	for (uint64_t i = 0; i < vdev_indirect_mapping_num_entries(vim); i++) {
 		vdev_indirect_mapping_entry_phys_t *vimep =
 		    &vim->vim_entries[i];
 		(void) printf("\t<%llx:%llx:%llx> -> "
 		    "<%llx:%llx:%llx> (%x obsolete)\n",
 		    (longlong_t)vd->vdev_id,
 		    (longlong_t)DVA_MAPPING_GET_SRC_OFFSET(vimep),
 		    (longlong_t)DVA_GET_ASIZE(&vimep->vimep_dst),
 		    (longlong_t)DVA_GET_VDEV(&vimep->vimep_dst),
 		    (longlong_t)DVA_GET_OFFSET(&vimep->vimep_dst),
 		    (longlong_t)DVA_GET_ASIZE(&vimep->vimep_dst),
 		    counts[i]);
 	}
 	(void) printf("\n");
 
 	uint64_t obsolete_sm_object;
 	VERIFY0(vdev_obsolete_sm_object(vd, &obsolete_sm_object));
 	if (obsolete_sm_object != 0) {
 		objset_t *mos = vd->vdev_spa->spa_meta_objset;
 		(void) printf("obsolete space map object %llu:\n",
 		    (u_longlong_t)obsolete_sm_object);
 		ASSERT(vd->vdev_obsolete_sm != NULL);
 		ASSERT3U(space_map_object(vd->vdev_obsolete_sm), ==,
 		    obsolete_sm_object);
 		dump_spacemap(mos, vd->vdev_obsolete_sm);
 		(void) printf("\n");
 	}
 }
 
 static void
 dump_metaslabs(spa_t *spa)
 {
 	vdev_t *vd, *rvd = spa->spa_root_vdev;
 	uint64_t m, c = 0, children = rvd->vdev_children;
 
 	(void) printf("\nMetaslabs:\n");
 
 	if (!dump_opt['d'] && zopt_metaslab_args > 0) {
 		c = zopt_metaslab[0];
 
 		if (c >= children)
 			(void) fatal("bad vdev id: %llu", (u_longlong_t)c);
 
 		if (zopt_metaslab_args > 1) {
 			vd = rvd->vdev_child[c];
 			print_vdev_metaslab_header(vd);
 
 			for (m = 1; m < zopt_metaslab_args; m++) {
 				if (zopt_metaslab[m] < vd->vdev_ms_count)
 					dump_metaslab(
 					    vd->vdev_ms[zopt_metaslab[m]]);
 				else
 					(void) fprintf(stderr, "bad metaslab "
 					    "number %llu\n",
 					    (u_longlong_t)zopt_metaslab[m]);
 			}
 			(void) printf("\n");
 			return;
 		}
 		children = c + 1;
 	}
 	for (; c < children; c++) {
 		vd = rvd->vdev_child[c];
 		print_vdev_metaslab_header(vd);
 
 		print_vdev_indirect(vd);
 
 		for (m = 0; m < vd->vdev_ms_count; m++)
 			dump_metaslab(vd->vdev_ms[m]);
 		(void) printf("\n");
 	}
 }
 
 static void
 dump_log_spacemaps(spa_t *spa)
 {
 	if (!spa_feature_is_active(spa, SPA_FEATURE_LOG_SPACEMAP))
 		return;
 
 	(void) printf("\nLog Space Maps in Pool:\n");
 	for (spa_log_sm_t *sls = avl_first(&spa->spa_sm_logs_by_txg);
 	    sls; sls = AVL_NEXT(&spa->spa_sm_logs_by_txg, sls)) {
 		space_map_t *sm = NULL;
 		VERIFY0(space_map_open(&sm, spa_meta_objset(spa),
 		    sls->sls_sm_obj, 0, UINT64_MAX, SPA_MINBLOCKSHIFT));
 
 		(void) printf("Log Spacemap object %llu txg %llu\n",
 		    (u_longlong_t)sls->sls_sm_obj, (u_longlong_t)sls->sls_txg);
 		dump_spacemap(spa->spa_meta_objset, sm);
 		space_map_close(sm);
 	}
 	(void) printf("\n");
 }
 
 static void
 dump_dde(const ddt_t *ddt, const ddt_entry_t *dde, uint64_t index)
 {
 	const ddt_phys_t *ddp = dde->dde_phys;
 	const ddt_key_t *ddk = &dde->dde_key;
 	const char *types[4] = { "ditto", "single", "double", "triple" };
 	char blkbuf[BP_SPRINTF_LEN];
 	blkptr_t blk;
 	int p;
 
 	for (p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
 		if (ddp->ddp_phys_birth == 0)
 			continue;
 		ddt_bp_create(ddt->ddt_checksum, ddk, ddp, &blk);
 		snprintf_blkptr(blkbuf, sizeof (blkbuf), &blk);
 		(void) printf("index %llx refcnt %llu %s %s\n",
 		    (u_longlong_t)index, (u_longlong_t)ddp->ddp_refcnt,
 		    types[p], blkbuf);
 	}
 }
 
 static void
 dump_dedup_ratio(const ddt_stat_t *dds)
 {
 	double rL, rP, rD, D, dedup, compress, copies;
 
 	if (dds->dds_blocks == 0)
 		return;
 
 	rL = (double)dds->dds_ref_lsize;
 	rP = (double)dds->dds_ref_psize;
 	rD = (double)dds->dds_ref_dsize;
 	D = (double)dds->dds_dsize;
 
 	dedup = rD / D;
 	compress = rL / rP;
 	copies = rD / rP;
 
 	(void) printf("dedup = %.2f, compress = %.2f, copies = %.2f, "
 	    "dedup * compress / copies = %.2f\n\n",
 	    dedup, compress, copies, dedup * compress / copies);
 }
 
 static void
 dump_ddt(ddt_t *ddt, enum ddt_type type, enum ddt_class class)
 {
 	char name[DDT_NAMELEN];
 	ddt_entry_t dde;
 	uint64_t walk = 0;
 	dmu_object_info_t doi;
 	uint64_t count, dspace, mspace;
 	int error;
 
 	error = ddt_object_info(ddt, type, class, &doi);
 
 	if (error == ENOENT)
 		return;
 	ASSERT(error == 0);
 
 	error = ddt_object_count(ddt, type, class, &count);
 	ASSERT(error == 0);
 	if (count == 0)
 		return;
 
 	dspace = doi.doi_physical_blocks_512 << 9;
 	mspace = doi.doi_fill_count * doi.doi_data_block_size;
 
 	ddt_object_name(ddt, type, class, name);
 
 	(void) printf("%s: %llu entries, size %llu on disk, %llu in core\n",
 	    name,
 	    (u_longlong_t)count,
 	    (u_longlong_t)(dspace / count),
 	    (u_longlong_t)(mspace / count));
 
 	if (dump_opt['D'] < 3)
 		return;
 
 	zpool_dump_ddt(NULL, &ddt->ddt_histogram[type][class]);
 
 	if (dump_opt['D'] < 4)
 		return;
 
 	if (dump_opt['D'] < 5 && class == DDT_CLASS_UNIQUE)
 		return;
 
 	(void) printf("%s contents:\n\n", name);
 
 	while ((error = ddt_object_walk(ddt, type, class, &walk, &dde)) == 0)
 		dump_dde(ddt, &dde, walk);
 
 	ASSERT3U(error, ==, ENOENT);
 
 	(void) printf("\n");
 }
 
 static void
 dump_all_ddts(spa_t *spa)
 {
 	ddt_histogram_t ddh_total = {{{0}}};
 	ddt_stat_t dds_total = {0};
 
 	for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
 		ddt_t *ddt = spa->spa_ddt[c];
 		for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
 			for (enum ddt_class class = 0; class < DDT_CLASSES;
 			    class++) {
 				dump_ddt(ddt, type, class);
 			}
 		}
 	}
 
 	ddt_get_dedup_stats(spa, &dds_total);
 
 	if (dds_total.dds_blocks == 0) {
 		(void) printf("All DDTs are empty\n");
 		return;
 	}
 
 	(void) printf("\n");
 
 	if (dump_opt['D'] > 1) {
 		(void) printf("DDT histogram (aggregated over all DDTs):\n");
 		ddt_get_dedup_histogram(spa, &ddh_total);
 		zpool_dump_ddt(&dds_total, &ddh_total);
 	}
 
 	dump_dedup_ratio(&dds_total);
 }
 
 static void
 dump_brt(spa_t *spa)
 {
 	if (!spa_feature_is_enabled(spa, SPA_FEATURE_BLOCK_CLONING)) {
 		printf("BRT: unsupported on this pool\n");
 		return;
 	}
 
 	if (!spa_feature_is_active(spa, SPA_FEATURE_BLOCK_CLONING)) {
 		printf("BRT: empty\n");
 		return;
 	}
 
 	brt_t *brt = spa->spa_brt;
 	VERIFY(brt);
 
 	char count[32], used[32], saved[32];
 	zdb_nicebytes(brt_get_used(spa), used, sizeof (used));
 	zdb_nicebytes(brt_get_saved(spa), saved, sizeof (saved));
 	uint64_t ratio = brt_get_ratio(spa);
 	printf("BRT: used %s; saved %s; ratio %llu.%02llux\n", used, saved,
 	    (u_longlong_t)(ratio / 100), (u_longlong_t)(ratio % 100));
 
 	if (dump_opt['T'] < 2)
 		return;
 
 	for (uint64_t vdevid = 0; vdevid < brt->brt_nvdevs; vdevid++) {
 		brt_vdev_t *brtvd = &brt->brt_vdevs[vdevid];
 		if (brtvd == NULL)
 			continue;
 
 		if (!brtvd->bv_initiated) {
 			printf("BRT: vdev %" PRIu64 ": empty\n", vdevid);
 			continue;
 		}
 
 		zdb_nicenum(brtvd->bv_totalcount, count, sizeof (count));
 		zdb_nicebytes(brtvd->bv_usedspace, used, sizeof (used));
 		zdb_nicebytes(brtvd->bv_savedspace, saved, sizeof (saved));
 		printf("BRT: vdev %" PRIu64 ": refcnt %s; used %s; saved %s\n",
 		    vdevid, count, used, saved);
 	}
 
 	if (dump_opt['T'] < 3)
 		return;
 
 	char dva[64];
 	printf("\n%-16s %-10s\n", "DVA", "REFCNT");
 
 	for (uint64_t vdevid = 0; vdevid < brt->brt_nvdevs; vdevid++) {
 		brt_vdev_t *brtvd = &brt->brt_vdevs[vdevid];
 		if (brtvd == NULL || !brtvd->bv_initiated)
 			continue;
 
 		zap_cursor_t zc;
 		zap_attribute_t za;
 		for (zap_cursor_init(&zc, brt->brt_mos, brtvd->bv_mos_entries);
 		    zap_cursor_retrieve(&zc, &za) == 0;
 		    zap_cursor_advance(&zc)) {
 			uint64_t offset = *(uint64_t *)za.za_name;
 			uint64_t refcnt = za.za_first_integer;
 
 			snprintf(dva, sizeof (dva), "%" PRIu64 ":%llx", vdevid,
 			    (u_longlong_t)offset);
 			printf("%-16s %-10llu\n", dva, (u_longlong_t)refcnt);
 		}
 		zap_cursor_fini(&zc);
 	}
 }
 
 static void
 dump_dtl_seg(void *arg, uint64_t start, uint64_t size)
 {
 	char *prefix = arg;
 
 	(void) printf("%s [%llu,%llu) length %llu\n",
 	    prefix,
 	    (u_longlong_t)start,
 	    (u_longlong_t)(start + size),
 	    (u_longlong_t)(size));
 }
 
 static void
 dump_dtl(vdev_t *vd, int indent)
 {
 	spa_t *spa = vd->vdev_spa;
 	boolean_t required;
 	const char *name[DTL_TYPES] = { "missing", "partial", "scrub",
 		"outage" };
 	char prefix[256];
 
 	spa_vdev_state_enter(spa, SCL_NONE);
 	required = vdev_dtl_required(vd);
 	(void) spa_vdev_state_exit(spa, NULL, 0);
 
 	if (indent == 0)
 		(void) printf("\nDirty time logs:\n\n");
 
 	(void) printf("\t%*s%s [%s]\n", indent, "",
 	    vd->vdev_path ? vd->vdev_path :
 	    vd->vdev_parent ? vd->vdev_ops->vdev_op_type : spa_name(spa),
 	    required ? "DTL-required" : "DTL-expendable");
 
 	for (int t = 0; t < DTL_TYPES; t++) {
 		range_tree_t *rt = vd->vdev_dtl[t];
 		if (range_tree_space(rt) == 0)
 			continue;
 		(void) snprintf(prefix, sizeof (prefix), "\t%*s%s",
 		    indent + 2, "", name[t]);
 		range_tree_walk(rt, dump_dtl_seg, prefix);
 		if (dump_opt['d'] > 5 && vd->vdev_children == 0)
 			dump_spacemap(spa->spa_meta_objset,
 			    vd->vdev_dtl_sm);
 	}
 
 	for (unsigned c = 0; c < vd->vdev_children; c++)
 		dump_dtl(vd->vdev_child[c], indent + 4);
 }
 
 static void
 dump_history(spa_t *spa)
 {
 	nvlist_t **events = NULL;
 	char *buf;
 	uint64_t resid, len, off = 0;
 	uint_t num = 0;
 	int error;
 	char tbuf[30];
 
 	if ((buf = malloc(SPA_OLD_MAXBLOCKSIZE)) == NULL) {
 		(void) fprintf(stderr, "%s: unable to allocate I/O buffer\n",
 		    __func__);
 		return;
 	}
 
 	do {
 		len = SPA_OLD_MAXBLOCKSIZE;
 
 		if ((error = spa_history_get(spa, &off, &len, buf)) != 0) {
 			(void) fprintf(stderr, "Unable to read history: "
 			    "error %d\n", error);
 			free(buf);
 			return;
 		}
 
 		if (zpool_history_unpack(buf, len, &resid, &events, &num) != 0)
 			break;
 
 		off -= resid;
 	} while (len != 0);
 
 	(void) printf("\nHistory:\n");
 	for (unsigned i = 0; i < num; i++) {
 		boolean_t printed = B_FALSE;
 
 		if (nvlist_exists(events[i], ZPOOL_HIST_TIME)) {
 			time_t tsec;
 			struct tm t;
 
 			tsec = fnvlist_lookup_uint64(events[i],
 			    ZPOOL_HIST_TIME);
 			(void) localtime_r(&tsec, &t);
 			(void) strftime(tbuf, sizeof (tbuf), "%F.%T", &t);
 		} else {
 			tbuf[0] = '\0';
 		}
 
 		if (nvlist_exists(events[i], ZPOOL_HIST_CMD)) {
 			(void) printf("%s %s\n", tbuf,
 			    fnvlist_lookup_string(events[i], ZPOOL_HIST_CMD));
 		} else if (nvlist_exists(events[i], ZPOOL_HIST_INT_EVENT)) {
 			uint64_t ievent;
 
 			ievent = fnvlist_lookup_uint64(events[i],
 			    ZPOOL_HIST_INT_EVENT);
 			if (ievent >= ZFS_NUM_LEGACY_HISTORY_EVENTS)
 				goto next;
 
 			(void) printf(" %s [internal %s txg:%ju] %s\n",
 			    tbuf,
 			    zfs_history_event_names[ievent],
 			    fnvlist_lookup_uint64(events[i],
 			    ZPOOL_HIST_TXG),
 			    fnvlist_lookup_string(events[i],
 			    ZPOOL_HIST_INT_STR));
 		} else if (nvlist_exists(events[i], ZPOOL_HIST_INT_NAME)) {
 			(void) printf("%s [txg:%ju] %s", tbuf,
 			    fnvlist_lookup_uint64(events[i],
 			    ZPOOL_HIST_TXG),
 			    fnvlist_lookup_string(events[i],
 			    ZPOOL_HIST_INT_NAME));
 
 			if (nvlist_exists(events[i], ZPOOL_HIST_DSNAME)) {
 				(void) printf(" %s (%llu)",
 				    fnvlist_lookup_string(events[i],
 				    ZPOOL_HIST_DSNAME),
 				    (u_longlong_t)fnvlist_lookup_uint64(
 				    events[i],
 				    ZPOOL_HIST_DSID));
 			}
 
 			(void) printf(" %s\n", fnvlist_lookup_string(events[i],
 			    ZPOOL_HIST_INT_STR));
 		} else if (nvlist_exists(events[i], ZPOOL_HIST_IOCTL)) {
 			(void) printf("%s ioctl %s\n", tbuf,
 			    fnvlist_lookup_string(events[i],
 			    ZPOOL_HIST_IOCTL));
 
 			if (nvlist_exists(events[i], ZPOOL_HIST_INPUT_NVL)) {
 				(void) printf("    input:\n");
 				dump_nvlist(fnvlist_lookup_nvlist(events[i],
 				    ZPOOL_HIST_INPUT_NVL), 8);
 			}
 			if (nvlist_exists(events[i], ZPOOL_HIST_OUTPUT_NVL)) {
 				(void) printf("    output:\n");
 				dump_nvlist(fnvlist_lookup_nvlist(events[i],
 				    ZPOOL_HIST_OUTPUT_NVL), 8);
 			}
 			if (nvlist_exists(events[i], ZPOOL_HIST_ERRNO)) {
 				(void) printf("    errno: %lld\n",
 				    (longlong_t)fnvlist_lookup_int64(events[i],
 				    ZPOOL_HIST_ERRNO));
 			}
 		} else {
 			goto next;
 		}
 
 		printed = B_TRUE;
 next:
 		if (dump_opt['h'] > 1) {
 			if (!printed)
 				(void) printf("unrecognized record:\n");
 			dump_nvlist(events[i], 2);
 		}
 	}
 	free(buf);
 }
 
 static void
 dump_dnode(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) os, (void) object, (void) data, (void) size;
 }
 
 static uint64_t
 blkid2offset(const dnode_phys_t *dnp, const blkptr_t *bp,
     const zbookmark_phys_t *zb)
 {
 	if (dnp == NULL) {
 		ASSERT(zb->zb_level < 0);
 		if (zb->zb_object == 0)
 			return (zb->zb_blkid);
 		return (zb->zb_blkid * BP_GET_LSIZE(bp));
 	}
 
 	ASSERT(zb->zb_level >= 0);
 
 	return ((zb->zb_blkid <<
 	    (zb->zb_level * (dnp->dn_indblkshift - SPA_BLKPTRSHIFT))) *
 	    dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT);
 }
 
 static void
 snprintf_zstd_header(spa_t *spa, char *blkbuf, size_t buflen,
     const blkptr_t *bp)
 {
 	static abd_t *pabd = NULL;
 	void *buf;
 	zio_t *zio;
 	zfs_zstdhdr_t zstd_hdr;
 	int error;
 
 	if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_ZSTD)
 		return;
 
 	if (BP_IS_HOLE(bp))
 		return;
 
 	if (BP_IS_EMBEDDED(bp)) {
 		buf = malloc(SPA_MAXBLOCKSIZE);
 		if (buf == NULL) {
 			(void) fprintf(stderr, "out of memory\n");
 			exit(1);
 		}
 		decode_embedded_bp_compressed(bp, buf);
 		memcpy(&zstd_hdr, buf, sizeof (zstd_hdr));
 		free(buf);
 		zstd_hdr.c_len = BE_32(zstd_hdr.c_len);
 		zstd_hdr.raw_version_level = BE_32(zstd_hdr.raw_version_level);
 		(void) snprintf(blkbuf + strlen(blkbuf),
 		    buflen - strlen(blkbuf),
 		    " ZSTD:size=%u:version=%u:level=%u:EMBEDDED",
 		    zstd_hdr.c_len, zfs_get_hdrversion(&zstd_hdr),
 		    zfs_get_hdrlevel(&zstd_hdr));
 		return;
 	}
 
 	if (!pabd)
 		pabd = abd_alloc_for_io(SPA_MAXBLOCKSIZE, B_FALSE);
 	zio = zio_root(spa, NULL, NULL, 0);
 
 	/* Decrypt but don't decompress so we can read the compression header */
 	zio_nowait(zio_read(zio, spa, bp, pabd, BP_GET_PSIZE(bp), NULL, NULL,
 	    ZIO_PRIORITY_SYNC_READ, ZIO_FLAG_CANFAIL | ZIO_FLAG_RAW_COMPRESS,
 	    NULL));
 	error = zio_wait(zio);
 	if (error) {
 		(void) fprintf(stderr, "read failed: %d\n", error);
 		return;
 	}
 	buf = abd_borrow_buf_copy(pabd, BP_GET_LSIZE(bp));
 	memcpy(&zstd_hdr, buf, sizeof (zstd_hdr));
 	zstd_hdr.c_len = BE_32(zstd_hdr.c_len);
 	zstd_hdr.raw_version_level = BE_32(zstd_hdr.raw_version_level);
 
 	(void) snprintf(blkbuf + strlen(blkbuf),
 	    buflen - strlen(blkbuf),
 	    " ZSTD:size=%u:version=%u:level=%u:NORMAL",
 	    zstd_hdr.c_len, zfs_get_hdrversion(&zstd_hdr),
 	    zfs_get_hdrlevel(&zstd_hdr));
 
 	abd_return_buf_copy(pabd, buf, BP_GET_LSIZE(bp));
 }
 
 static void
 snprintf_blkptr_compact(char *blkbuf, size_t buflen, const blkptr_t *bp,
     boolean_t bp_freed)
 {
 	const dva_t *dva = bp->blk_dva;
 	int ndvas = dump_opt['d'] > 5 ? BP_GET_NDVAS(bp) : 1;
 	int i;
 
 	if (dump_opt['b'] >= 6) {
 		snprintf_blkptr(blkbuf, buflen, bp);
 		if (bp_freed) {
 			(void) snprintf(blkbuf + strlen(blkbuf),
 			    buflen - strlen(blkbuf), " %s", "FREE");
 		}
 		return;
 	}
 
 	if (BP_IS_EMBEDDED(bp)) {
 		(void) sprintf(blkbuf,
 		    "EMBEDDED et=%u %llxL/%llxP B=%llu",
 		    (int)BPE_GET_ETYPE(bp),
 		    (u_longlong_t)BPE_GET_LSIZE(bp),
 		    (u_longlong_t)BPE_GET_PSIZE(bp),
 		    (u_longlong_t)bp->blk_birth);
 		return;
 	}
 
 	blkbuf[0] = '\0';
 
 	for (i = 0; i < ndvas; i++)
 		(void) snprintf(blkbuf + strlen(blkbuf),
 		    buflen - strlen(blkbuf), "%llu:%llx:%llx ",
 		    (u_longlong_t)DVA_GET_VDEV(&dva[i]),
 		    (u_longlong_t)DVA_GET_OFFSET(&dva[i]),
 		    (u_longlong_t)DVA_GET_ASIZE(&dva[i]));
 
 	if (BP_IS_HOLE(bp)) {
 		(void) snprintf(blkbuf + strlen(blkbuf),
 		    buflen - strlen(blkbuf),
 		    "%llxL B=%llu",
 		    (u_longlong_t)BP_GET_LSIZE(bp),
 		    (u_longlong_t)bp->blk_birth);
 	} else {
 		(void) snprintf(blkbuf + strlen(blkbuf),
 		    buflen - strlen(blkbuf),
 		    "%llxL/%llxP F=%llu B=%llu/%llu",
 		    (u_longlong_t)BP_GET_LSIZE(bp),
 		    (u_longlong_t)BP_GET_PSIZE(bp),
 		    (u_longlong_t)BP_GET_FILL(bp),
 		    (u_longlong_t)bp->blk_birth,
 		    (u_longlong_t)BP_PHYSICAL_BIRTH(bp));
 		if (bp_freed)
 			(void) snprintf(blkbuf + strlen(blkbuf),
 			    buflen - strlen(blkbuf), " %s", "FREE");
 		(void) snprintf(blkbuf + strlen(blkbuf),
 		    buflen - strlen(blkbuf),
 		    " cksum=%016llx:%016llx:%016llx:%016llx",
 		    (u_longlong_t)bp->blk_cksum.zc_word[0],
 		    (u_longlong_t)bp->blk_cksum.zc_word[1],
 		    (u_longlong_t)bp->blk_cksum.zc_word[2],
 		    (u_longlong_t)bp->blk_cksum.zc_word[3]);
 	}
 }
 
 static void
 print_indirect(spa_t *spa, blkptr_t *bp, const zbookmark_phys_t *zb,
     const dnode_phys_t *dnp)
 {
 	char blkbuf[BP_SPRINTF_LEN];
 	int l;
 
 	if (!BP_IS_EMBEDDED(bp)) {
 		ASSERT3U(BP_GET_TYPE(bp), ==, dnp->dn_type);
 		ASSERT3U(BP_GET_LEVEL(bp), ==, zb->zb_level);
 	}
 
 	(void) printf("%16llx ", (u_longlong_t)blkid2offset(dnp, bp, zb));
 
 	ASSERT(zb->zb_level >= 0);
 
 	for (l = dnp->dn_nlevels - 1; l >= -1; l--) {
 		if (l == zb->zb_level) {
 			(void) printf("L%llx", (u_longlong_t)zb->zb_level);
 		} else {
 			(void) printf(" ");
 		}
 	}
 
 	snprintf_blkptr_compact(blkbuf, sizeof (blkbuf), bp, B_FALSE);
 	if (dump_opt['Z'] && BP_GET_COMPRESS(bp) == ZIO_COMPRESS_ZSTD)
 		snprintf_zstd_header(spa, blkbuf, sizeof (blkbuf), bp);
 	(void) printf("%s\n", blkbuf);
 }
 
 static int
 visit_indirect(spa_t *spa, const dnode_phys_t *dnp,
     blkptr_t *bp, const zbookmark_phys_t *zb)
 {
 	int err = 0;
 
 	if (bp->blk_birth == 0)
 		return (0);
 
 	print_indirect(spa, bp, zb, dnp);
 
 	if (BP_GET_LEVEL(bp) > 0 && !BP_IS_HOLE(bp)) {
 		arc_flags_t flags = ARC_FLAG_WAIT;
 		int i;
 		blkptr_t *cbp;
 		int epb = BP_GET_LSIZE(bp) >> SPA_BLKPTRSHIFT;
 		arc_buf_t *buf;
 		uint64_t fill = 0;
 		ASSERT(!BP_IS_REDACTED(bp));
 
 		err = arc_read(NULL, spa, bp, arc_getbuf_func, &buf,
 		    ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb);
 		if (err)
 			return (err);
 		ASSERT(buf->b_data);
 
 		/* recursively visit blocks below this */
 		cbp = buf->b_data;
 		for (i = 0; i < epb; i++, cbp++) {
 			zbookmark_phys_t czb;
 
 			SET_BOOKMARK(&czb, zb->zb_objset, zb->zb_object,
 			    zb->zb_level - 1,
 			    zb->zb_blkid * epb + i);
 			err = visit_indirect(spa, dnp, cbp, &czb);
 			if (err)
 				break;
 			fill += BP_GET_FILL(cbp);
 		}
 		if (!err)
 			ASSERT3U(fill, ==, BP_GET_FILL(bp));
 		arc_buf_destroy(buf, &buf);
 	}
 
 	return (err);
 }
 
 static void
 dump_indirect(dnode_t *dn)
 {
 	dnode_phys_t *dnp = dn->dn_phys;
 	zbookmark_phys_t czb;
 
 	(void) printf("Indirect blocks:\n");
 
 	SET_BOOKMARK(&czb, dmu_objset_id(dn->dn_objset),
 	    dn->dn_object, dnp->dn_nlevels - 1, 0);
 	for (int j = 0; j < dnp->dn_nblkptr; j++) {
 		czb.zb_blkid = j;
 		(void) visit_indirect(dmu_objset_spa(dn->dn_objset), dnp,
 		    &dnp->dn_blkptr[j], &czb);
 	}
 
 	(void) printf("\n");
 }
 
 static void
 dump_dsl_dir(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) os, (void) object;
 	dsl_dir_phys_t *dd = data;
 	time_t crtime;
 	char nice[32];
 
 	/* make sure nicenum has enough space */
 	_Static_assert(sizeof (nice) >= NN_NUMBUF_SZ, "nice truncated");
 
 	if (dd == NULL)
 		return;
 
 	ASSERT3U(size, >=, sizeof (dsl_dir_phys_t));
 
 	crtime = dd->dd_creation_time;
 	(void) printf("\t\tcreation_time = %s", ctime(&crtime));
 	(void) printf("\t\thead_dataset_obj = %llu\n",
 	    (u_longlong_t)dd->dd_head_dataset_obj);
 	(void) printf("\t\tparent_dir_obj = %llu\n",
 	    (u_longlong_t)dd->dd_parent_obj);
 	(void) printf("\t\torigin_obj = %llu\n",
 	    (u_longlong_t)dd->dd_origin_obj);
 	(void) printf("\t\tchild_dir_zapobj = %llu\n",
 	    (u_longlong_t)dd->dd_child_dir_zapobj);
 	zdb_nicenum(dd->dd_used_bytes, nice, sizeof (nice));
 	(void) printf("\t\tused_bytes = %s\n", nice);
 	zdb_nicenum(dd->dd_compressed_bytes, nice, sizeof (nice));
 	(void) printf("\t\tcompressed_bytes = %s\n", nice);
 	zdb_nicenum(dd->dd_uncompressed_bytes, nice, sizeof (nice));
 	(void) printf("\t\tuncompressed_bytes = %s\n", nice);
 	zdb_nicenum(dd->dd_quota, nice, sizeof (nice));
 	(void) printf("\t\tquota = %s\n", nice);
 	zdb_nicenum(dd->dd_reserved, nice, sizeof (nice));
 	(void) printf("\t\treserved = %s\n", nice);
 	(void) printf("\t\tprops_zapobj = %llu\n",
 	    (u_longlong_t)dd->dd_props_zapobj);
 	(void) printf("\t\tdeleg_zapobj = %llu\n",
 	    (u_longlong_t)dd->dd_deleg_zapobj);
 	(void) printf("\t\tflags = %llx\n",
 	    (u_longlong_t)dd->dd_flags);
 
 #define	DO(which) \
 	zdb_nicenum(dd->dd_used_breakdown[DD_USED_ ## which], nice, \
 	    sizeof (nice)); \
 	(void) printf("\t\tused_breakdown[" #which "] = %s\n", nice)
 	DO(HEAD);
 	DO(SNAP);
 	DO(CHILD);
 	DO(CHILD_RSRV);
 	DO(REFRSRV);
 #undef DO
 	(void) printf("\t\tclones = %llu\n",
 	    (u_longlong_t)dd->dd_clones);
 }
 
 static void
 dump_dsl_dataset(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) os, (void) object;
 	dsl_dataset_phys_t *ds = data;
 	time_t crtime;
 	char used[32], compressed[32], uncompressed[32], unique[32];
 	char blkbuf[BP_SPRINTF_LEN];
 
 	/* make sure nicenum has enough space */
 	_Static_assert(sizeof (used) >= NN_NUMBUF_SZ, "used truncated");
 	_Static_assert(sizeof (compressed) >= NN_NUMBUF_SZ,
 	    "compressed truncated");
 	_Static_assert(sizeof (uncompressed) >= NN_NUMBUF_SZ,
 	    "uncompressed truncated");
 	_Static_assert(sizeof (unique) >= NN_NUMBUF_SZ, "unique truncated");
 
 	if (ds == NULL)
 		return;
 
 	ASSERT(size == sizeof (*ds));
 	crtime = ds->ds_creation_time;
 	zdb_nicenum(ds->ds_referenced_bytes, used, sizeof (used));
 	zdb_nicenum(ds->ds_compressed_bytes, compressed, sizeof (compressed));
 	zdb_nicenum(ds->ds_uncompressed_bytes, uncompressed,
 	    sizeof (uncompressed));
 	zdb_nicenum(ds->ds_unique_bytes, unique, sizeof (unique));
 	snprintf_blkptr(blkbuf, sizeof (blkbuf), &ds->ds_bp);
 
 	(void) printf("\t\tdir_obj = %llu\n",
 	    (u_longlong_t)ds->ds_dir_obj);
 	(void) printf("\t\tprev_snap_obj = %llu\n",
 	    (u_longlong_t)ds->ds_prev_snap_obj);
 	(void) printf("\t\tprev_snap_txg = %llu\n",
 	    (u_longlong_t)ds->ds_prev_snap_txg);
 	(void) printf("\t\tnext_snap_obj = %llu\n",
 	    (u_longlong_t)ds->ds_next_snap_obj);
 	(void) printf("\t\tsnapnames_zapobj = %llu\n",
 	    (u_longlong_t)ds->ds_snapnames_zapobj);
 	(void) printf("\t\tnum_children = %llu\n",
 	    (u_longlong_t)ds->ds_num_children);
 	(void) printf("\t\tuserrefs_obj = %llu\n",
 	    (u_longlong_t)ds->ds_userrefs_obj);
 	(void) printf("\t\tcreation_time = %s", ctime(&crtime));
 	(void) printf("\t\tcreation_txg = %llu\n",
 	    (u_longlong_t)ds->ds_creation_txg);
 	(void) printf("\t\tdeadlist_obj = %llu\n",
 	    (u_longlong_t)ds->ds_deadlist_obj);
 	(void) printf("\t\tused_bytes = %s\n", used);
 	(void) printf("\t\tcompressed_bytes = %s\n", compressed);
 	(void) printf("\t\tuncompressed_bytes = %s\n", uncompressed);
 	(void) printf("\t\tunique = %s\n", unique);
 	(void) printf("\t\tfsid_guid = %llu\n",
 	    (u_longlong_t)ds->ds_fsid_guid);
 	(void) printf("\t\tguid = %llu\n",
 	    (u_longlong_t)ds->ds_guid);
 	(void) printf("\t\tflags = %llx\n",
 	    (u_longlong_t)ds->ds_flags);
 	(void) printf("\t\tnext_clones_obj = %llu\n",
 	    (u_longlong_t)ds->ds_next_clones_obj);
 	(void) printf("\t\tprops_obj = %llu\n",
 	    (u_longlong_t)ds->ds_props_obj);
 	(void) printf("\t\tbp = %s\n", blkbuf);
 }
 
 static int
 dump_bptree_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
 {
 	(void) arg, (void) tx;
 	char blkbuf[BP_SPRINTF_LEN];
 
 	if (bp->blk_birth != 0) {
 		snprintf_blkptr(blkbuf, sizeof (blkbuf), bp);
 		(void) printf("\t%s\n", blkbuf);
 	}
 	return (0);
 }
 
 static void
 dump_bptree(objset_t *os, uint64_t obj, const char *name)
 {
 	char bytes[32];
 	bptree_phys_t *bt;
 	dmu_buf_t *db;
 
 	/* make sure nicenum has enough space */
 	_Static_assert(sizeof (bytes) >= NN_NUMBUF_SZ, "bytes truncated");
 
 	if (dump_opt['d'] < 3)
 		return;
 
 	VERIFY3U(0, ==, dmu_bonus_hold(os, obj, FTAG, &db));
 	bt = db->db_data;
 	zdb_nicenum(bt->bt_bytes, bytes, sizeof (bytes));
 	(void) printf("\n    %s: %llu datasets, %s\n",
 	    name, (unsigned long long)(bt->bt_end - bt->bt_begin), bytes);
 	dmu_buf_rele(db, FTAG);
 
 	if (dump_opt['d'] < 5)
 		return;
 
 	(void) printf("\n");
 
 	(void) bptree_iterate(os, obj, B_FALSE, dump_bptree_cb, NULL, NULL);
 }
 
 static int
 dump_bpobj_cb(void *arg, const blkptr_t *bp, boolean_t bp_freed, dmu_tx_t *tx)
 {
 	(void) arg, (void) tx;
 	char blkbuf[BP_SPRINTF_LEN];
 
 	ASSERT(bp->blk_birth != 0);
 	snprintf_blkptr_compact(blkbuf, sizeof (blkbuf), bp, bp_freed);
 	(void) printf("\t%s\n", blkbuf);
 	return (0);
 }
 
 static void
 dump_full_bpobj(bpobj_t *bpo, const char *name, int indent)
 {
 	char bytes[32];
 	char comp[32];
 	char uncomp[32];
 	uint64_t i;
 
 	/* make sure nicenum has enough space */
 	_Static_assert(sizeof (bytes) >= NN_NUMBUF_SZ, "bytes truncated");
 	_Static_assert(sizeof (comp) >= NN_NUMBUF_SZ, "comp truncated");
 	_Static_assert(sizeof (uncomp) >= NN_NUMBUF_SZ, "uncomp truncated");
 
 	if (dump_opt['d'] < 3)
 		return;
 
 	zdb_nicenum(bpo->bpo_phys->bpo_bytes, bytes, sizeof (bytes));
 	if (bpo->bpo_havesubobj && bpo->bpo_phys->bpo_subobjs != 0) {
 		zdb_nicenum(bpo->bpo_phys->bpo_comp, comp, sizeof (comp));
 		zdb_nicenum(bpo->bpo_phys->bpo_uncomp, uncomp, sizeof (uncomp));
 		if (bpo->bpo_havefreed) {
 			(void) printf("    %*s: object %llu, %llu local "
 			    "blkptrs, %llu freed, %llu subobjs in object %llu, "
 			    "%s (%s/%s comp)\n",
 			    indent * 8, name,
 			    (u_longlong_t)bpo->bpo_object,
 			    (u_longlong_t)bpo->bpo_phys->bpo_num_blkptrs,
 			    (u_longlong_t)bpo->bpo_phys->bpo_num_freed,
 			    (u_longlong_t)bpo->bpo_phys->bpo_num_subobjs,
 			    (u_longlong_t)bpo->bpo_phys->bpo_subobjs,
 			    bytes, comp, uncomp);
 		} else {
 			(void) printf("    %*s: object %llu, %llu local "
 			    "blkptrs, %llu subobjs in object %llu, "
 			    "%s (%s/%s comp)\n",
 			    indent * 8, name,
 			    (u_longlong_t)bpo->bpo_object,
 			    (u_longlong_t)bpo->bpo_phys->bpo_num_blkptrs,
 			    (u_longlong_t)bpo->bpo_phys->bpo_num_subobjs,
 			    (u_longlong_t)bpo->bpo_phys->bpo_subobjs,
 			    bytes, comp, uncomp);
 		}
 
 		for (i = 0; i < bpo->bpo_phys->bpo_num_subobjs; i++) {
 			uint64_t subobj;
 			bpobj_t subbpo;
 			int error;
 			VERIFY0(dmu_read(bpo->bpo_os,
 			    bpo->bpo_phys->bpo_subobjs,
 			    i * sizeof (subobj), sizeof (subobj), &subobj, 0));
 			error = bpobj_open(&subbpo, bpo->bpo_os, subobj);
 			if (error != 0) {
 				(void) printf("ERROR %u while trying to open "
 				    "subobj id %llu\n",
 				    error, (u_longlong_t)subobj);
 				continue;
 			}
 			dump_full_bpobj(&subbpo, "subobj", indent + 1);
 			bpobj_close(&subbpo);
 		}
 	} else {
 		if (bpo->bpo_havefreed) {
 			(void) printf("    %*s: object %llu, %llu blkptrs, "
 			    "%llu freed, %s\n",
 			    indent * 8, name,
 			    (u_longlong_t)bpo->bpo_object,
 			    (u_longlong_t)bpo->bpo_phys->bpo_num_blkptrs,
 			    (u_longlong_t)bpo->bpo_phys->bpo_num_freed,
 			    bytes);
 		} else {
 			(void) printf("    %*s: object %llu, %llu blkptrs, "
 			    "%s\n",
 			    indent * 8, name,
 			    (u_longlong_t)bpo->bpo_object,
 			    (u_longlong_t)bpo->bpo_phys->bpo_num_blkptrs,
 			    bytes);
 		}
 	}
 
 	if (dump_opt['d'] < 5)
 		return;
 
 
 	if (indent == 0) {
 		(void) bpobj_iterate_nofree(bpo, dump_bpobj_cb, NULL, NULL);
 		(void) printf("\n");
 	}
 }
 
 static int
 dump_bookmark(dsl_pool_t *dp, char *name, boolean_t print_redact,
     boolean_t print_list)
 {
 	int err = 0;
 	zfs_bookmark_phys_t prop;
 	objset_t *mos = dp->dp_spa->spa_meta_objset;
 	err = dsl_bookmark_lookup(dp, name, NULL, &prop);
 
 	if (err != 0) {
 		return (err);
 	}
 
 	(void) printf("\t#%s: ", strchr(name, '#') + 1);
 	(void) printf("{guid: %llx creation_txg: %llu creation_time: "
 	    "%llu redaction_obj: %llu}\n", (u_longlong_t)prop.zbm_guid,
 	    (u_longlong_t)prop.zbm_creation_txg,
 	    (u_longlong_t)prop.zbm_creation_time,
 	    (u_longlong_t)prop.zbm_redaction_obj);
 
 	IMPLY(print_list, print_redact);
 	if (!print_redact || prop.zbm_redaction_obj == 0)
 		return (0);
 
 	redaction_list_t *rl;
 	VERIFY0(dsl_redaction_list_hold_obj(dp,
 	    prop.zbm_redaction_obj, FTAG, &rl));
 
 	redaction_list_phys_t *rlp = rl->rl_phys;
 	(void) printf("\tRedacted:\n\t\tProgress: ");
 	if (rlp->rlp_last_object != UINT64_MAX ||
 	    rlp->rlp_last_blkid != UINT64_MAX) {
 		(void) printf("%llu %llu (incomplete)\n",
 		    (u_longlong_t)rlp->rlp_last_object,
 		    (u_longlong_t)rlp->rlp_last_blkid);
 	} else {
 		(void) printf("complete\n");
 	}
 	(void) printf("\t\tSnapshots: [");
 	for (unsigned int i = 0; i < rlp->rlp_num_snaps; i++) {
 		if (i > 0)
 			(void) printf(", ");
 		(void) printf("%0llu",
 		    (u_longlong_t)rlp->rlp_snaps[i]);
 	}
 	(void) printf("]\n\t\tLength: %llu\n",
 	    (u_longlong_t)rlp->rlp_num_entries);
 
 	if (!print_list) {
 		dsl_redaction_list_rele(rl, FTAG);
 		return (0);
 	}
 
 	if (rlp->rlp_num_entries == 0) {
 		dsl_redaction_list_rele(rl, FTAG);
 		(void) printf("\t\tRedaction List: []\n\n");
 		return (0);
 	}
 
 	redact_block_phys_t *rbp_buf;
 	uint64_t size;
 	dmu_object_info_t doi;
 
 	VERIFY0(dmu_object_info(mos, prop.zbm_redaction_obj, &doi));
 	size = doi.doi_max_offset;
 	rbp_buf = kmem_alloc(size, KM_SLEEP);
 
 	err = dmu_read(mos, prop.zbm_redaction_obj, 0, size,
 	    rbp_buf, 0);
 	if (err != 0) {
 		dsl_redaction_list_rele(rl, FTAG);
 		kmem_free(rbp_buf, size);
 		return (err);
 	}
 
 	(void) printf("\t\tRedaction List: [{object: %llx, offset: "
 	    "%llx, blksz: %x, count: %llx}",
 	    (u_longlong_t)rbp_buf[0].rbp_object,
 	    (u_longlong_t)rbp_buf[0].rbp_blkid,
 	    (uint_t)(redact_block_get_size(&rbp_buf[0])),
 	    (u_longlong_t)redact_block_get_count(&rbp_buf[0]));
 
 	for (size_t i = 1; i < rlp->rlp_num_entries; i++) {
 		(void) printf(",\n\t\t{object: %llx, offset: %llx, "
 		    "blksz: %x, count: %llx}",
 		    (u_longlong_t)rbp_buf[i].rbp_object,
 		    (u_longlong_t)rbp_buf[i].rbp_blkid,
 		    (uint_t)(redact_block_get_size(&rbp_buf[i])),
 		    (u_longlong_t)redact_block_get_count(&rbp_buf[i]));
 	}
 	dsl_redaction_list_rele(rl, FTAG);
 	kmem_free(rbp_buf, size);
 	(void) printf("]\n\n");
 	return (0);
 }
 
 static void
 dump_bookmarks(objset_t *os, int verbosity)
 {
 	zap_cursor_t zc;
 	zap_attribute_t attr;
 	dsl_dataset_t *ds = dmu_objset_ds(os);
 	dsl_pool_t *dp = spa_get_dsl(os->os_spa);
 	objset_t *mos = os->os_spa->spa_meta_objset;
 	if (verbosity < 4)
 		return;
 	dsl_pool_config_enter(dp, FTAG);
 
 	for (zap_cursor_init(&zc, mos, ds->ds_bookmarks_obj);
 	    zap_cursor_retrieve(&zc, &attr) == 0;
 	    zap_cursor_advance(&zc)) {
 		char osname[ZFS_MAX_DATASET_NAME_LEN];
 		char buf[ZFS_MAX_DATASET_NAME_LEN];
 		int len;
 		dmu_objset_name(os, osname);
 		len = snprintf(buf, sizeof (buf), "%s#%s", osname,
 		    attr.za_name);
 		VERIFY3S(len, <, ZFS_MAX_DATASET_NAME_LEN);
 		(void) dump_bookmark(dp, buf, verbosity >= 5, verbosity >= 6);
 	}
 	zap_cursor_fini(&zc);
 	dsl_pool_config_exit(dp, FTAG);
 }
 
 static void
 bpobj_count_refd(bpobj_t *bpo)
 {
 	mos_obj_refd(bpo->bpo_object);
 
 	if (bpo->bpo_havesubobj && bpo->bpo_phys->bpo_subobjs != 0) {
 		mos_obj_refd(bpo->bpo_phys->bpo_subobjs);
 		for (uint64_t i = 0; i < bpo->bpo_phys->bpo_num_subobjs; i++) {
 			uint64_t subobj;
 			bpobj_t subbpo;
 			int error;
 			VERIFY0(dmu_read(bpo->bpo_os,
 			    bpo->bpo_phys->bpo_subobjs,
 			    i * sizeof (subobj), sizeof (subobj), &subobj, 0));
 			error = bpobj_open(&subbpo, bpo->bpo_os, subobj);
 			if (error != 0) {
 				(void) printf("ERROR %u while trying to open "
 				    "subobj id %llu\n",
 				    error, (u_longlong_t)subobj);
 				continue;
 			}
 			bpobj_count_refd(&subbpo);
 			bpobj_close(&subbpo);
 		}
 	}
 }
 
 static int
 dsl_deadlist_entry_count_refd(void *arg, dsl_deadlist_entry_t *dle)
 {
 	spa_t *spa = arg;
 	uint64_t empty_bpobj = spa->spa_dsl_pool->dp_empty_bpobj;
 	if (dle->dle_bpobj.bpo_object != empty_bpobj)
 		bpobj_count_refd(&dle->dle_bpobj);
 	return (0);
 }
 
 static int
 dsl_deadlist_entry_dump(void *arg, dsl_deadlist_entry_t *dle)
 {
 	ASSERT(arg == NULL);
 	if (dump_opt['d'] >= 5) {
 		char buf[128];
 		(void) snprintf(buf, sizeof (buf),
 		    "mintxg %llu -> obj %llu",
 		    (longlong_t)dle->dle_mintxg,
 		    (longlong_t)dle->dle_bpobj.bpo_object);
 
 		dump_full_bpobj(&dle->dle_bpobj, buf, 0);
 	} else {
 		(void) printf("mintxg %llu -> obj %llu\n",
 		    (longlong_t)dle->dle_mintxg,
 		    (longlong_t)dle->dle_bpobj.bpo_object);
 	}
 	return (0);
 }
 
 static void
 dump_blkptr_list(dsl_deadlist_t *dl, const char *name)
 {
 	char bytes[32];
 	char comp[32];
 	char uncomp[32];
 	char entries[32];
 	spa_t *spa = dmu_objset_spa(dl->dl_os);
 	uint64_t empty_bpobj = spa->spa_dsl_pool->dp_empty_bpobj;
 
 	if (dl->dl_oldfmt) {
 		if (dl->dl_bpobj.bpo_object != empty_bpobj)
 			bpobj_count_refd(&dl->dl_bpobj);
 	} else {
 		mos_obj_refd(dl->dl_object);
 		dsl_deadlist_iterate(dl, dsl_deadlist_entry_count_refd, spa);
 	}
 
 	/* make sure nicenum has enough space */
 	_Static_assert(sizeof (bytes) >= NN_NUMBUF_SZ, "bytes truncated");
 	_Static_assert(sizeof (comp) >= NN_NUMBUF_SZ, "comp truncated");
 	_Static_assert(sizeof (uncomp) >= NN_NUMBUF_SZ, "uncomp truncated");
 	_Static_assert(sizeof (entries) >= NN_NUMBUF_SZ, "entries truncated");
 
 	if (dump_opt['d'] < 3)
 		return;
 
 	if (dl->dl_oldfmt) {
 		dump_full_bpobj(&dl->dl_bpobj, "old-format deadlist", 0);
 		return;
 	}
 
 	zdb_nicenum(dl->dl_phys->dl_used, bytes, sizeof (bytes));
 	zdb_nicenum(dl->dl_phys->dl_comp, comp, sizeof (comp));
 	zdb_nicenum(dl->dl_phys->dl_uncomp, uncomp, sizeof (uncomp));
 	zdb_nicenum(avl_numnodes(&dl->dl_tree), entries, sizeof (entries));
 	(void) printf("\n    %s: %s (%s/%s comp), %s entries\n",
 	    name, bytes, comp, uncomp, entries);
 
 	if (dump_opt['d'] < 4)
 		return;
 
 	(void) putchar('\n');
 
 	dsl_deadlist_iterate(dl, dsl_deadlist_entry_dump, NULL);
 }
 
 static int
 verify_dd_livelist(objset_t *os)
 {
 	uint64_t ll_used, used, ll_comp, comp, ll_uncomp, uncomp;
 	dsl_pool_t *dp = spa_get_dsl(os->os_spa);
 	dsl_dir_t  *dd = os->os_dsl_dataset->ds_dir;
 
 	ASSERT(!dmu_objset_is_snapshot(os));
 	if (!dsl_deadlist_is_open(&dd->dd_livelist))
 		return (0);
 
 	/* Iterate through the livelist to check for duplicates */
 	dsl_deadlist_iterate(&dd->dd_livelist, sublivelist_verify_lightweight,
 	    NULL);
 
 	dsl_pool_config_enter(dp, FTAG);
 	dsl_deadlist_space(&dd->dd_livelist, &ll_used,
 	    &ll_comp, &ll_uncomp);
 
 	dsl_dataset_t *origin_ds;
 	ASSERT(dsl_pool_config_held(dp));
 	VERIFY0(dsl_dataset_hold_obj(dp,
 	    dsl_dir_phys(dd)->dd_origin_obj, FTAG, &origin_ds));
 	VERIFY0(dsl_dataset_space_written(origin_ds, os->os_dsl_dataset,
 	    &used, &comp, &uncomp));
 	dsl_dataset_rele(origin_ds, FTAG);
 	dsl_pool_config_exit(dp, FTAG);
 	/*
 	 *  It's possible that the dataset's uncomp space is larger than the
 	 *  livelist's because livelists do not track embedded block pointers
 	 */
 	if (used != ll_used || comp != ll_comp || uncomp < ll_uncomp) {
 		char nice_used[32], nice_comp[32], nice_uncomp[32];
 		(void) printf("Discrepancy in space accounting:\n");
 		zdb_nicenum(used, nice_used, sizeof (nice_used));
 		zdb_nicenum(comp, nice_comp, sizeof (nice_comp));
 		zdb_nicenum(uncomp, nice_uncomp, sizeof (nice_uncomp));
 		(void) printf("dir: used %s, comp %s, uncomp %s\n",
 		    nice_used, nice_comp, nice_uncomp);
 		zdb_nicenum(ll_used, nice_used, sizeof (nice_used));
 		zdb_nicenum(ll_comp, nice_comp, sizeof (nice_comp));
 		zdb_nicenum(ll_uncomp, nice_uncomp, sizeof (nice_uncomp));
 		(void) printf("livelist: used %s, comp %s, uncomp %s\n",
 		    nice_used, nice_comp, nice_uncomp);
 		return (1);
 	}
 	return (0);
 }
 
 static char *key_material = NULL;
 
 static boolean_t
 zdb_derive_key(dsl_dir_t *dd, uint8_t *key_out)
 {
 	uint64_t keyformat, salt, iters;
 	int i;
 	unsigned char c;
 
 	VERIFY0(zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
 	    zfs_prop_to_name(ZFS_PROP_KEYFORMAT), sizeof (uint64_t),
 	    1, &keyformat));
 
 	switch (keyformat) {
 	case ZFS_KEYFORMAT_HEX:
 		for (i = 0; i < WRAPPING_KEY_LEN * 2; i += 2) {
 			if (!isxdigit(key_material[i]) ||
 			    !isxdigit(key_material[i+1]))
 				return (B_FALSE);
 			if (sscanf(&key_material[i], "%02hhx", &c) != 1)
 				return (B_FALSE);
 			key_out[i / 2] = c;
 		}
 		break;
 
 	case ZFS_KEYFORMAT_PASSPHRASE:
 		VERIFY0(zap_lookup(dd->dd_pool->dp_meta_objset,
 		    dd->dd_crypto_obj, zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT),
 		    sizeof (uint64_t), 1, &salt));
 		VERIFY0(zap_lookup(dd->dd_pool->dp_meta_objset,
 		    dd->dd_crypto_obj, zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS),
 		    sizeof (uint64_t), 1, &iters));
 
 		if (PKCS5_PBKDF2_HMAC_SHA1(key_material, strlen(key_material),
 		    ((uint8_t *)&salt), sizeof (uint64_t), iters,
 		    WRAPPING_KEY_LEN, key_out) != 1)
 			return (B_FALSE);
 
 		break;
 
 	default:
 		fatal("no support for key format %u\n",
 		    (unsigned int) keyformat);
 	}
 
 	return (B_TRUE);
 }
 
 static char encroot[ZFS_MAX_DATASET_NAME_LEN];
 static boolean_t key_loaded = B_FALSE;
 
 static void
 zdb_load_key(objset_t *os)
 {
 	dsl_pool_t *dp;
 	dsl_dir_t *dd, *rdd;
 	uint8_t key[WRAPPING_KEY_LEN];
 	uint64_t rddobj;
 	int err;
 
 	dp = spa_get_dsl(os->os_spa);
 	dd = os->os_dsl_dataset->ds_dir;
 
 	dsl_pool_config_enter(dp, FTAG);
 	VERIFY0(zap_lookup(dd->dd_pool->dp_meta_objset, dd->dd_crypto_obj,
 	    DSL_CRYPTO_KEY_ROOT_DDOBJ, sizeof (uint64_t), 1, &rddobj));
 	VERIFY0(dsl_dir_hold_obj(dd->dd_pool, rddobj, NULL, FTAG, &rdd));
 	dsl_dir_name(rdd, encroot);
 	dsl_dir_rele(rdd, FTAG);
 
 	if (!zdb_derive_key(dd, key))
 		fatal("couldn't derive encryption key");
 
 	dsl_pool_config_exit(dp, FTAG);
 
 	ASSERT3U(dsl_dataset_get_keystatus(dd), ==, ZFS_KEYSTATUS_UNAVAILABLE);
 
 	dsl_crypto_params_t *dcp;
 	nvlist_t *crypto_args;
 
 	crypto_args = fnvlist_alloc();
 	fnvlist_add_uint8_array(crypto_args, "wkeydata",
 	    (uint8_t *)key, WRAPPING_KEY_LEN);
 	VERIFY0(dsl_crypto_params_create_nvlist(DCP_CMD_NONE,
 	    NULL, crypto_args, &dcp));
 	err = spa_keystore_load_wkey(encroot, dcp, B_FALSE);
 
 	dsl_crypto_params_free(dcp, (err != 0));
 	fnvlist_free(crypto_args);
 
 	if (err != 0)
 		fatal(
 		    "couldn't load encryption key for %s: %s",
 		    encroot, err == ZFS_ERR_CRYPTO_NOTSUP ?
 		    "crypto params not supported" : strerror(err));
 
 	ASSERT3U(dsl_dataset_get_keystatus(dd), ==, ZFS_KEYSTATUS_AVAILABLE);
 
 	printf("Unlocked encryption root: %s\n", encroot);
 	key_loaded = B_TRUE;
 }
 
 static void
 zdb_unload_key(void)
 {
 	if (!key_loaded)
 		return;
 
 	VERIFY0(spa_keystore_unload_wkey(encroot));
 	key_loaded = B_FALSE;
 }
 
 static avl_tree_t idx_tree;
 static avl_tree_t domain_tree;
 static boolean_t fuid_table_loaded;
 static objset_t *sa_os = NULL;
 static sa_attr_type_t *sa_attr_table = NULL;
 
 static int
 open_objset(const char *path, const void *tag, objset_t **osp)
 {
 	int err;
 	uint64_t sa_attrs = 0;
 	uint64_t version = 0;
 
 	VERIFY3P(sa_os, ==, NULL);
 
 	/*
 	 * We can't own an objset if it's redacted.  Therefore, we do this
 	 * dance: hold the objset, then acquire a long hold on its dataset, then
 	 * release the pool (which is held as part of holding the objset).
 	 */
 
 	if (dump_opt['K']) {
 		/* decryption requested, try to load keys */
 		err = dmu_objset_hold(path, tag, osp);
 		if (err != 0) {
 			(void) fprintf(stderr, "failed to hold dataset "
 			    "'%s': %s\n",
 			    path, strerror(err));
 			return (err);
 		}
 		dsl_dataset_long_hold(dmu_objset_ds(*osp), tag);
 		dsl_pool_rele(dmu_objset_pool(*osp), tag);
 
 		/* succeeds or dies */
 		zdb_load_key(*osp);
 
 		/* release it all */
 		dsl_dataset_long_rele(dmu_objset_ds(*osp), tag);
 		dsl_dataset_rele(dmu_objset_ds(*osp), tag);
 	}
 
 	int ds_hold_flags = key_loaded ? DS_HOLD_FLAG_DECRYPT : 0;
 
 	err = dmu_objset_hold_flags(path, ds_hold_flags, tag, osp);
 	if (err != 0) {
 		(void) fprintf(stderr, "failed to hold dataset '%s': %s\n",
 		    path, strerror(err));
 		return (err);
 	}
 	dsl_dataset_long_hold(dmu_objset_ds(*osp), tag);
 	dsl_pool_rele(dmu_objset_pool(*osp), tag);
 
 	if (dmu_objset_type(*osp) == DMU_OST_ZFS &&
 	    (key_loaded || !(*osp)->os_encrypted)) {
 		(void) zap_lookup(*osp, MASTER_NODE_OBJ, ZPL_VERSION_STR,
 		    8, 1, &version);
 		if (version >= ZPL_VERSION_SA) {
 			(void) zap_lookup(*osp, MASTER_NODE_OBJ, ZFS_SA_ATTRS,
 			    8, 1, &sa_attrs);
 		}
 		err = sa_setup(*osp, sa_attrs, zfs_attr_table, ZPL_END,
 		    &sa_attr_table);
 		if (err != 0) {
 			(void) fprintf(stderr, "sa_setup failed: %s\n",
 			    strerror(err));
 			dsl_dataset_long_rele(dmu_objset_ds(*osp), tag);
 			dsl_dataset_rele_flags(dmu_objset_ds(*osp),
 			    ds_hold_flags, tag);
 			*osp = NULL;
 		}
 	}
 	sa_os = *osp;
 
 	return (err);
 }
 
 static void
 close_objset(objset_t *os, const void *tag)
 {
 	VERIFY3P(os, ==, sa_os);
 	if (os->os_sa != NULL)
 		sa_tear_down(os);
 	dsl_dataset_long_rele(dmu_objset_ds(os), tag);
 	dsl_dataset_rele_flags(dmu_objset_ds(os),
 	    key_loaded ? DS_HOLD_FLAG_DECRYPT : 0, tag);
 	sa_attr_table = NULL;
 	sa_os = NULL;
 
 	zdb_unload_key();
 }
 
 static void
 fuid_table_destroy(void)
 {
 	if (fuid_table_loaded) {
 		zfs_fuid_table_destroy(&idx_tree, &domain_tree);
 		fuid_table_loaded = B_FALSE;
 	}
 }
 
 /*
  * print uid or gid information.
  * For normal POSIX id just the id is printed in decimal format.
  * For CIFS files with FUID the fuid is printed in hex followed by
  * the domain-rid string.
  */
 static void
 print_idstr(uint64_t id, const char *id_type)
 {
 	if (FUID_INDEX(id)) {
 		const char *domain =
 		    zfs_fuid_idx_domain(&idx_tree, FUID_INDEX(id));
 		(void) printf("\t%s     %llx [%s-%d]\n", id_type,
 		    (u_longlong_t)id, domain, (int)FUID_RID(id));
 	} else {
 		(void) printf("\t%s     %llu\n", id_type, (u_longlong_t)id);
 	}
 
 }
 
 static void
 dump_uidgid(objset_t *os, uint64_t uid, uint64_t gid)
 {
 	uint32_t uid_idx, gid_idx;
 
 	uid_idx = FUID_INDEX(uid);
 	gid_idx = FUID_INDEX(gid);
 
 	/* Load domain table, if not already loaded */
 	if (!fuid_table_loaded && (uid_idx || gid_idx)) {
 		uint64_t fuid_obj;
 
 		/* first find the fuid object.  It lives in the master node */
 		VERIFY(zap_lookup(os, MASTER_NODE_OBJ, ZFS_FUID_TABLES,
 		    8, 1, &fuid_obj) == 0);
 		zfs_fuid_avl_tree_create(&idx_tree, &domain_tree);
 		(void) zfs_fuid_table_load(os, fuid_obj,
 		    &idx_tree, &domain_tree);
 		fuid_table_loaded = B_TRUE;
 	}
 
 	print_idstr(uid, "uid");
 	print_idstr(gid, "gid");
 }
 
 static void
 dump_znode_sa_xattr(sa_handle_t *hdl)
 {
 	nvlist_t *sa_xattr;
 	nvpair_t *elem = NULL;
 	int sa_xattr_size = 0;
 	int sa_xattr_entries = 0;
 	int error;
 	char *sa_xattr_packed;
 
 	error = sa_size(hdl, sa_attr_table[ZPL_DXATTR], &sa_xattr_size);
 	if (error || sa_xattr_size == 0)
 		return;
 
 	sa_xattr_packed = malloc(sa_xattr_size);
 	if (sa_xattr_packed == NULL)
 		return;
 
 	error = sa_lookup(hdl, sa_attr_table[ZPL_DXATTR],
 	    sa_xattr_packed, sa_xattr_size);
 	if (error) {
 		free(sa_xattr_packed);
 		return;
 	}
 
 	error = nvlist_unpack(sa_xattr_packed, sa_xattr_size, &sa_xattr, 0);
 	if (error) {
 		free(sa_xattr_packed);
 		return;
 	}
 
 	while ((elem = nvlist_next_nvpair(sa_xattr, elem)) != NULL)
 		sa_xattr_entries++;
 
 	(void) printf("\tSA xattrs: %d bytes, %d entries\n\n",
 	    sa_xattr_size, sa_xattr_entries);
 	while ((elem = nvlist_next_nvpair(sa_xattr, elem)) != NULL) {
 		boolean_t can_print = !dump_opt['P'];
 		uchar_t *value;
 		uint_t cnt, idx;
 
 		(void) printf("\t\t%s = ", nvpair_name(elem));
 		nvpair_value_byte_array(elem, &value, &cnt);
 
 		for (idx = 0; idx < cnt; ++idx) {
 			if (!isprint(value[idx])) {
 				can_print = B_FALSE;
 				break;
 			}
 		}
 
 		for (idx = 0; idx < cnt; ++idx) {
 			if (can_print)
 				(void) putchar(value[idx]);
 			else
 				(void) printf("\\%3.3o", value[idx]);
 		}
 		(void) putchar('\n');
 	}
 
 	nvlist_free(sa_xattr);
 	free(sa_xattr_packed);
 }
 
 static void
 dump_znode_symlink(sa_handle_t *hdl)
 {
 	int sa_symlink_size = 0;
 	char linktarget[MAXPATHLEN];
 	int error;
 
 	error = sa_size(hdl, sa_attr_table[ZPL_SYMLINK], &sa_symlink_size);
 	if (error || sa_symlink_size == 0) {
 		return;
 	}
 	if (sa_symlink_size >= sizeof (linktarget)) {
 		(void) printf("symlink size %d is too large\n",
 		    sa_symlink_size);
 		return;
 	}
 	linktarget[sa_symlink_size] = '\0';
 	if (sa_lookup(hdl, sa_attr_table[ZPL_SYMLINK],
 	    &linktarget, sa_symlink_size) == 0)
 		(void) printf("\ttarget	%s\n", linktarget);
 }
 
 static void
 dump_znode(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) data, (void) size;
 	char path[MAXPATHLEN * 2];	/* allow for xattr and failure prefix */
 	sa_handle_t *hdl;
 	uint64_t xattr, rdev, gen;
 	uint64_t uid, gid, mode, fsize, parent, links;
 	uint64_t pflags;
 	uint64_t acctm[2], modtm[2], chgtm[2], crtm[2];
 	time_t z_crtime, z_atime, z_mtime, z_ctime;
 	sa_bulk_attr_t bulk[12];
 	int idx = 0;
 	int error;
 
 	VERIFY3P(os, ==, sa_os);
 	if (sa_handle_get(os, object, NULL, SA_HDL_PRIVATE, &hdl)) {
 		(void) printf("Failed to get handle for SA znode\n");
 		return;
 	}
 
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_UID], NULL, &uid, 8);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_GID], NULL, &gid, 8);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_LINKS], NULL,
 	    &links, 8);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_GEN], NULL, &gen, 8);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_MODE], NULL,
 	    &mode, 8);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_PARENT],
 	    NULL, &parent, 8);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_SIZE], NULL,
 	    &fsize, 8);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_ATIME], NULL,
 	    acctm, 16);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_MTIME], NULL,
 	    modtm, 16);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_CRTIME], NULL,
 	    crtm, 16);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_CTIME], NULL,
 	    chgtm, 16);
 	SA_ADD_BULK_ATTR(bulk, idx, sa_attr_table[ZPL_FLAGS], NULL,
 	    &pflags, 8);
 
 	if (sa_bulk_lookup(hdl, bulk, idx)) {
 		(void) sa_handle_destroy(hdl);
 		return;
 	}
 
 	z_crtime = (time_t)crtm[0];
 	z_atime = (time_t)acctm[0];
 	z_mtime = (time_t)modtm[0];
 	z_ctime = (time_t)chgtm[0];
 
 	if (dump_opt['d'] > 4) {
 		error = zfs_obj_to_path(os, object, path, sizeof (path));
 		if (error == ESTALE) {
 			(void) snprintf(path, sizeof (path), "on delete queue");
 		} else if (error != 0) {
 			leaked_objects++;
 			(void) snprintf(path, sizeof (path),
 			    "path not found, possibly leaked");
 		}
 		(void) printf("\tpath	%s\n", path);
 	}
 
 	if (S_ISLNK(mode))
 		dump_znode_symlink(hdl);
 	dump_uidgid(os, uid, gid);
 	(void) printf("\tatime	%s", ctime(&z_atime));
 	(void) printf("\tmtime	%s", ctime(&z_mtime));
 	(void) printf("\tctime	%s", ctime(&z_ctime));
 	(void) printf("\tcrtime	%s", ctime(&z_crtime));
 	(void) printf("\tgen	%llu\n", (u_longlong_t)gen);
 	(void) printf("\tmode	%llo\n", (u_longlong_t)mode);
 	(void) printf("\tsize	%llu\n", (u_longlong_t)fsize);
 	(void) printf("\tparent	%llu\n", (u_longlong_t)parent);
 	(void) printf("\tlinks	%llu\n", (u_longlong_t)links);
 	(void) printf("\tpflags	%llx\n", (u_longlong_t)pflags);
 	if (dmu_objset_projectquota_enabled(os) && (pflags & ZFS_PROJID)) {
 		uint64_t projid;
 
 		if (sa_lookup(hdl, sa_attr_table[ZPL_PROJID], &projid,
 		    sizeof (uint64_t)) == 0)
 			(void) printf("\tprojid	%llu\n", (u_longlong_t)projid);
 	}
 	if (sa_lookup(hdl, sa_attr_table[ZPL_XATTR], &xattr,
 	    sizeof (uint64_t)) == 0)
 		(void) printf("\txattr	%llu\n", (u_longlong_t)xattr);
 	if (sa_lookup(hdl, sa_attr_table[ZPL_RDEV], &rdev,
 	    sizeof (uint64_t)) == 0)
 		(void) printf("\trdev	0x%016llx\n", (u_longlong_t)rdev);
 	dump_znode_sa_xattr(hdl);
 	sa_handle_destroy(hdl);
 }
 
 static void
 dump_acl(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) os, (void) object, (void) data, (void) size;
 }
 
 static void
 dump_dmu_objset(objset_t *os, uint64_t object, void *data, size_t size)
 {
 	(void) os, (void) object, (void) data, (void) size;
 }
 
 static object_viewer_t *object_viewer[DMU_OT_NUMTYPES + 1] = {
 	dump_none,		/* unallocated			*/
 	dump_zap,		/* object directory		*/
 	dump_uint64,		/* object array			*/
 	dump_none,		/* packed nvlist		*/
 	dump_packed_nvlist,	/* packed nvlist size		*/
 	dump_none,		/* bpobj			*/
 	dump_bpobj,		/* bpobj header			*/
 	dump_none,		/* SPA space map header		*/
 	dump_none,		/* SPA space map		*/
 	dump_none,		/* ZIL intent log		*/
 	dump_dnode,		/* DMU dnode			*/
 	dump_dmu_objset,	/* DMU objset			*/
 	dump_dsl_dir,		/* DSL directory		*/
 	dump_zap,		/* DSL directory child map	*/
 	dump_zap,		/* DSL dataset snap map		*/
 	dump_zap,		/* DSL props			*/
 	dump_dsl_dataset,	/* DSL dataset			*/
 	dump_znode,		/* ZFS znode			*/
 	dump_acl,		/* ZFS V0 ACL			*/
 	dump_uint8,		/* ZFS plain file		*/
 	dump_zpldir,		/* ZFS directory		*/
 	dump_zap,		/* ZFS master node		*/
 	dump_zap,		/* ZFS delete queue		*/
 	dump_uint8,		/* zvol object			*/
 	dump_zap,		/* zvol prop			*/
 	dump_uint8,		/* other uint8[]		*/
 	dump_uint64,		/* other uint64[]		*/
 	dump_zap,		/* other ZAP			*/
 	dump_zap,		/* persistent error log		*/
 	dump_uint8,		/* SPA history			*/
 	dump_history_offsets,	/* SPA history offsets		*/
 	dump_zap,		/* Pool properties		*/
 	dump_zap,		/* DSL permissions		*/
 	dump_acl,		/* ZFS ACL			*/
 	dump_uint8,		/* ZFS SYSACL			*/
 	dump_none,		/* FUID nvlist			*/
 	dump_packed_nvlist,	/* FUID nvlist size		*/
 	dump_zap,		/* DSL dataset next clones	*/
 	dump_zap,		/* DSL scrub queue		*/
 	dump_zap,		/* ZFS user/group/project used	*/
 	dump_zap,		/* ZFS user/group/project quota	*/
 	dump_zap,		/* snapshot refcount tags	*/
 	dump_ddt_zap,		/* DDT ZAP object		*/
 	dump_zap,		/* DDT statistics		*/
 	dump_znode,		/* SA object			*/
 	dump_zap,		/* SA Master Node		*/
 	dump_sa_attrs,		/* SA attribute registration	*/
 	dump_sa_layouts,	/* SA attribute layouts		*/
 	dump_zap,		/* DSL scrub translations	*/
 	dump_none,		/* fake dedup BP		*/
 	dump_zap,		/* deadlist			*/
 	dump_none,		/* deadlist hdr			*/
 	dump_zap,		/* dsl clones			*/
 	dump_bpobj_subobjs,	/* bpobj subobjs		*/
 	dump_unknown,		/* Unknown type, must be last	*/
 };
 
 static boolean_t
 match_object_type(dmu_object_type_t obj_type, uint64_t flags)
 {
 	boolean_t match = B_TRUE;
 
 	switch (obj_type) {
 	case DMU_OT_DIRECTORY_CONTENTS:
 		if (!(flags & ZOR_FLAG_DIRECTORY))
 			match = B_FALSE;
 		break;
 	case DMU_OT_PLAIN_FILE_CONTENTS:
 		if (!(flags & ZOR_FLAG_PLAIN_FILE))
 			match = B_FALSE;
 		break;
 	case DMU_OT_SPACE_MAP:
 		if (!(flags & ZOR_FLAG_SPACE_MAP))
 			match = B_FALSE;
 		break;
 	default:
 		if (strcmp(zdb_ot_name(obj_type), "zap") == 0) {
 			if (!(flags & ZOR_FLAG_ZAP))
 				match = B_FALSE;
 			break;
 		}
 
 		/*
 		 * If all bits except some of the supported flags are
 		 * set, the user combined the all-types flag (A) with
 		 * a negated flag to exclude some types (e.g. A-f to
 		 * show all object types except plain files).
 		 */
 		if ((flags | ZOR_SUPPORTED_FLAGS) != ZOR_FLAG_ALL_TYPES)
 			match = B_FALSE;
 
 		break;
 	}
 
 	return (match);
 }
 
 static void
 dump_object(objset_t *os, uint64_t object, int verbosity,
     boolean_t *print_header, uint64_t *dnode_slots_used, uint64_t flags)
 {
 	dmu_buf_t *db = NULL;
 	dmu_object_info_t doi;
 	dnode_t *dn;
 	boolean_t dnode_held = B_FALSE;
 	void *bonus = NULL;
 	size_t bsize = 0;
 	char iblk[32], dblk[32], lsize[32], asize[32], fill[32], dnsize[32];
 	char bonus_size[32];
 	char aux[50];
 	int error;
 
 	/* make sure nicenum has enough space */
 	_Static_assert(sizeof (iblk) >= NN_NUMBUF_SZ, "iblk truncated");
 	_Static_assert(sizeof (dblk) >= NN_NUMBUF_SZ, "dblk truncated");
 	_Static_assert(sizeof (lsize) >= NN_NUMBUF_SZ, "lsize truncated");
 	_Static_assert(sizeof (asize) >= NN_NUMBUF_SZ, "asize truncated");
 	_Static_assert(sizeof (bonus_size) >= NN_NUMBUF_SZ,
 	    "bonus_size truncated");
 
 	if (*print_header) {
 		(void) printf("\n%10s  %3s  %5s  %5s  %5s  %6s  %5s  %6s  %s\n",
 		    "Object", "lvl", "iblk", "dblk", "dsize", "dnsize",
 		    "lsize", "%full", "type");
 		*print_header = 0;
 	}
 
 	if (object == 0) {
 		dn = DMU_META_DNODE(os);
 		dmu_object_info_from_dnode(dn, &doi);
 	} else {
 		/*
 		 * Encrypted datasets will have sensitive bonus buffers
 		 * encrypted. Therefore we cannot hold the bonus buffer and
 		 * must hold the dnode itself instead.
 		 */
 		error = dmu_object_info(os, object, &doi);
 		if (error)
 			fatal("dmu_object_info() failed, errno %u", error);
 
 		if (!key_loaded && os->os_encrypted &&
 		    DMU_OT_IS_ENCRYPTED(doi.doi_bonus_type)) {
 			error = dnode_hold(os, object, FTAG, &dn);
 			if (error)
 				fatal("dnode_hold() failed, errno %u", error);
 			dnode_held = B_TRUE;
 		} else {
 			error = dmu_bonus_hold(os, object, FTAG, &db);
 			if (error)
 				fatal("dmu_bonus_hold(%llu) failed, errno %u",
 				    object, error);
 			bonus = db->db_data;
 			bsize = db->db_size;
 			dn = DB_DNODE((dmu_buf_impl_t *)db);
 		}
 	}
 
 	/*
 	 * Default to showing all object types if no flags were specified.
 	 */
 	if (flags != 0 && flags != ZOR_FLAG_ALL_TYPES &&
 	    !match_object_type(doi.doi_type, flags))
 		goto out;
 
 	if (dnode_slots_used)
 		*dnode_slots_used = doi.doi_dnodesize / DNODE_MIN_SIZE;
 
 	zdb_nicenum(doi.doi_metadata_block_size, iblk, sizeof (iblk));
 	zdb_nicenum(doi.doi_data_block_size, dblk, sizeof (dblk));
 	zdb_nicenum(doi.doi_max_offset, lsize, sizeof (lsize));
 	zdb_nicenum(doi.doi_physical_blocks_512 << 9, asize, sizeof (asize));
 	zdb_nicenum(doi.doi_bonus_size, bonus_size, sizeof (bonus_size));
 	zdb_nicenum(doi.doi_dnodesize, dnsize, sizeof (dnsize));
 	(void) snprintf(fill, sizeof (fill), "%6.2f", 100.0 *
 	    doi.doi_fill_count * doi.doi_data_block_size / (object == 0 ?
 	    DNODES_PER_BLOCK : 1) / doi.doi_max_offset);
 
 	aux[0] = '\0';
 
 	if (doi.doi_checksum != ZIO_CHECKSUM_INHERIT || verbosity >= 6) {
 		(void) snprintf(aux + strlen(aux), sizeof (aux) - strlen(aux),
 		    " (K=%s)", ZDB_CHECKSUM_NAME(doi.doi_checksum));
 	}
 
 	if (doi.doi_compress == ZIO_COMPRESS_INHERIT &&
 	    ZIO_COMPRESS_HASLEVEL(os->os_compress) && verbosity >= 6) {
 		const char *compname = NULL;
 		if (zfs_prop_index_to_string(ZFS_PROP_COMPRESSION,
 		    ZIO_COMPRESS_RAW(os->os_compress, os->os_complevel),
 		    &compname) == 0) {
 			(void) snprintf(aux + strlen(aux),
 			    sizeof (aux) - strlen(aux), " (Z=inherit=%s)",
 			    compname);
 		} else {
 			(void) snprintf(aux + strlen(aux),
 			    sizeof (aux) - strlen(aux),
 			    " (Z=inherit=%s-unknown)",
 			    ZDB_COMPRESS_NAME(os->os_compress));
 		}
 	} else if (doi.doi_compress == ZIO_COMPRESS_INHERIT && verbosity >= 6) {
 		(void) snprintf(aux + strlen(aux), sizeof (aux) - strlen(aux),
 		    " (Z=inherit=%s)", ZDB_COMPRESS_NAME(os->os_compress));
 	} else if (doi.doi_compress != ZIO_COMPRESS_INHERIT || verbosity >= 6) {
 		(void) snprintf(aux + strlen(aux), sizeof (aux) - strlen(aux),
 		    " (Z=%s)", ZDB_COMPRESS_NAME(doi.doi_compress));
 	}
 
 	(void) printf("%10lld  %3u  %5s  %5s  %5s  %6s  %5s  %6s  %s%s\n",
 	    (u_longlong_t)object, doi.doi_indirection, iblk, dblk,
 	    asize, dnsize, lsize, fill, zdb_ot_name(doi.doi_type), aux);
 
 	if (doi.doi_bonus_type != DMU_OT_NONE && verbosity > 3) {
 		(void) printf("%10s  %3s  %5s  %5s  %5s  %5s  %5s  %6s  %s\n",
 		    "", "", "", "", "", "", bonus_size, "bonus",
 		    zdb_ot_name(doi.doi_bonus_type));
 	}
 
 	if (verbosity >= 4) {
 		(void) printf("\tdnode flags: %s%s%s%s\n",
 		    (dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) ?
 		    "USED_BYTES " : "",
 		    (dn->dn_phys->dn_flags & DNODE_FLAG_USERUSED_ACCOUNTED) ?
 		    "USERUSED_ACCOUNTED " : "",
 		    (dn->dn_phys->dn_flags & DNODE_FLAG_USEROBJUSED_ACCOUNTED) ?
 		    "USEROBJUSED_ACCOUNTED " : "",
 		    (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) ?
 		    "SPILL_BLKPTR" : "");
 		(void) printf("\tdnode maxblkid: %llu\n",
 		    (longlong_t)dn->dn_phys->dn_maxblkid);
 
 		if (!dnode_held) {
 			object_viewer[ZDB_OT_TYPE(doi.doi_bonus_type)](os,
 			    object, bonus, bsize);
 		} else {
 			(void) printf("\t\t(bonus encrypted)\n");
 		}
 
 		if (key_loaded ||
 		    (!os->os_encrypted || !DMU_OT_IS_ENCRYPTED(doi.doi_type))) {
 			object_viewer[ZDB_OT_TYPE(doi.doi_type)](os, object,
 			    NULL, 0);
 		} else {
 			(void) printf("\t\t(object encrypted)\n");
 		}
 
 		*print_header = B_TRUE;
 	}
 
 	if (verbosity >= 5) {
 		if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) {
 			char blkbuf[BP_SPRINTF_LEN];
 			snprintf_blkptr_compact(blkbuf, sizeof (blkbuf),
 			    DN_SPILL_BLKPTR(dn->dn_phys), B_FALSE);
 			(void) printf("\nSpill block: %s\n", blkbuf);
 		}
 		dump_indirect(dn);
 	}
 
 	if (verbosity >= 5) {
 		/*
 		 * Report the list of segments that comprise the object.
 		 */
 		uint64_t start = 0;
 		uint64_t end;
 		uint64_t blkfill = 1;
 		int minlvl = 1;
 
 		if (dn->dn_type == DMU_OT_DNODE) {
 			minlvl = 0;
 			blkfill = DNODES_PER_BLOCK;
 		}
 
 		for (;;) {
 			char segsize[32];
 			/* make sure nicenum has enough space */
 			_Static_assert(sizeof (segsize) >= NN_NUMBUF_SZ,
 			    "segsize truncated");
 			error = dnode_next_offset(dn,
 			    0, &start, minlvl, blkfill, 0);
 			if (error)
 				break;
 			end = start;
 			error = dnode_next_offset(dn,
 			    DNODE_FIND_HOLE, &end, minlvl, blkfill, 0);
 			zdb_nicenum(end - start, segsize, sizeof (segsize));
 			(void) printf("\t\tsegment [%016llx, %016llx)"
 			    " size %5s\n", (u_longlong_t)start,
 			    (u_longlong_t)end, segsize);
 			if (error)
 				break;
 			start = end;
 		}
 	}
 
 out:
 	if (db != NULL)
 		dmu_buf_rele(db, FTAG);
 	if (dnode_held)
 		dnode_rele(dn, FTAG);
 }
 
 static void
 count_dir_mos_objects(dsl_dir_t *dd)
 {
 	mos_obj_refd(dd->dd_object);
 	mos_obj_refd(dsl_dir_phys(dd)->dd_child_dir_zapobj);
 	mos_obj_refd(dsl_dir_phys(dd)->dd_deleg_zapobj);
 	mos_obj_refd(dsl_dir_phys(dd)->dd_props_zapobj);
 	mos_obj_refd(dsl_dir_phys(dd)->dd_clones);
 
 	/*
 	 * The dd_crypto_obj can be referenced by multiple dsl_dir's.
 	 * Ignore the references after the first one.
 	 */
 	mos_obj_refd_multiple(dd->dd_crypto_obj);
 }
 
 static void
 count_ds_mos_objects(dsl_dataset_t *ds)
 {
 	mos_obj_refd(ds->ds_object);
 	mos_obj_refd(dsl_dataset_phys(ds)->ds_next_clones_obj);
 	mos_obj_refd(dsl_dataset_phys(ds)->ds_props_obj);
 	mos_obj_refd(dsl_dataset_phys(ds)->ds_userrefs_obj);
 	mos_obj_refd(dsl_dataset_phys(ds)->ds_snapnames_zapobj);
 	mos_obj_refd(ds->ds_bookmarks_obj);
 
 	if (!dsl_dataset_is_snapshot(ds)) {
 		count_dir_mos_objects(ds->ds_dir);
 	}
 }
 
 static const char *const objset_types[DMU_OST_NUMTYPES] = {
 	"NONE", "META", "ZPL", "ZVOL", "OTHER", "ANY" };
 
 /*
  * Parse a string denoting a range of object IDs of the form
  * <start>[:<end>[:flags]], and store the results in zor.
  * Return 0 on success. On error, return 1 and update the msg
  * pointer to point to a descriptive error message.
  */
 static int
 parse_object_range(char *range, zopt_object_range_t *zor, const char **msg)
 {
 	uint64_t flags = 0;
 	char *p, *s, *dup, *flagstr, *tmp = NULL;
 	size_t len;
 	int i;
 	int rc = 0;
 
 	if (strchr(range, ':') == NULL) {
 		zor->zor_obj_start = strtoull(range, &p, 0);
 		if (*p != '\0') {
 			*msg = "Invalid characters in object ID";
 			rc = 1;
 		}
 		zor->zor_obj_start = ZDB_MAP_OBJECT_ID(zor->zor_obj_start);
 		zor->zor_obj_end = zor->zor_obj_start;
 		return (rc);
 	}
 
 	if (strchr(range, ':') == range) {
 		*msg = "Invalid leading colon";
 		rc = 1;
 		return (rc);
 	}
 
 	len = strlen(range);
 	if (range[len - 1] == ':') {
 		*msg = "Invalid trailing colon";
 		rc = 1;
 		return (rc);
 	}
 
 	dup = strdup(range);
 	s = strtok_r(dup, ":", &tmp);
 	zor->zor_obj_start = strtoull(s, &p, 0);
 
 	if (*p != '\0') {
 		*msg = "Invalid characters in start object ID";
 		rc = 1;
 		goto out;
 	}
 
 	s = strtok_r(NULL, ":", &tmp);
 	zor->zor_obj_end = strtoull(s, &p, 0);
 
 	if (*p != '\0') {
 		*msg = "Invalid characters in end object ID";
 		rc = 1;
 		goto out;
 	}
 
 	if (zor->zor_obj_start > zor->zor_obj_end) {
 		*msg = "Start object ID may not exceed end object ID";
 		rc = 1;
 		goto out;
 	}
 
 	s = strtok_r(NULL, ":", &tmp);
 	if (s == NULL) {
 		zor->zor_flags = ZOR_FLAG_ALL_TYPES;
 		goto out;
 	} else if (strtok_r(NULL, ":", &tmp) != NULL) {
 		*msg = "Invalid colon-delimited field after flags";
 		rc = 1;
 		goto out;
 	}
 
 	flagstr = s;
 	for (i = 0; flagstr[i]; i++) {
 		int bit;
 		boolean_t negation = (flagstr[i] == '-');
 
 		if (negation) {
 			i++;
 			if (flagstr[i] == '\0') {
 				*msg = "Invalid trailing negation operator";
 				rc = 1;
 				goto out;
 			}
 		}
 		bit = flagbits[(uchar_t)flagstr[i]];
 		if (bit == 0) {
 			*msg = "Invalid flag";
 			rc = 1;
 			goto out;
 		}
 		if (negation)
 			flags &= ~bit;
 		else
 			flags |= bit;
 	}
 	zor->zor_flags = flags;
 
 	zor->zor_obj_start = ZDB_MAP_OBJECT_ID(zor->zor_obj_start);
 	zor->zor_obj_end = ZDB_MAP_OBJECT_ID(zor->zor_obj_end);
 
 out:
 	free(dup);
 	return (rc);
 }
 
 static void
 dump_objset(objset_t *os)
 {
 	dmu_objset_stats_t dds = { 0 };
 	uint64_t object, object_count;
 	uint64_t refdbytes, usedobjs, scratch;
 	char numbuf[32];
 	char blkbuf[BP_SPRINTF_LEN + 20];
 	char osname[ZFS_MAX_DATASET_NAME_LEN];
 	const char *type = "UNKNOWN";
 	int verbosity = dump_opt['d'];
 	boolean_t print_header;
 	unsigned i;
 	int error;
 	uint64_t total_slots_used = 0;
 	uint64_t max_slot_used = 0;
 	uint64_t dnode_slots;
 	uint64_t obj_start;
 	uint64_t obj_end;
 	uint64_t flags;
 
 	/* make sure nicenum has enough space */
 	_Static_assert(sizeof (numbuf) >= NN_NUMBUF_SZ, "numbuf truncated");
 
 	dsl_pool_config_enter(dmu_objset_pool(os), FTAG);
 	dmu_objset_fast_stat(os, &dds);
 	dsl_pool_config_exit(dmu_objset_pool(os), FTAG);
 
 	print_header = B_TRUE;
 
 	if (dds.dds_type < DMU_OST_NUMTYPES)
 		type = objset_types[dds.dds_type];
 
 	if (dds.dds_type == DMU_OST_META) {
 		dds.dds_creation_txg = TXG_INITIAL;
 		usedobjs = BP_GET_FILL(os->os_rootbp);
 		refdbytes = dsl_dir_phys(os->os_spa->spa_dsl_pool->dp_mos_dir)->
 		    dd_used_bytes;
 	} else {
 		dmu_objset_space(os, &refdbytes, &scratch, &usedobjs, &scratch);
 	}
 
 	ASSERT3U(usedobjs, ==, BP_GET_FILL(os->os_rootbp));
 
 	zdb_nicenum(refdbytes, numbuf, sizeof (numbuf));
 
 	if (verbosity >= 4) {
 		(void) snprintf(blkbuf, sizeof (blkbuf), ", rootbp ");
 		(void) snprintf_blkptr(blkbuf + strlen(blkbuf),
 		    sizeof (blkbuf) - strlen(blkbuf), os->os_rootbp);
 	} else {
 		blkbuf[0] = '\0';
 	}
 
 	dmu_objset_name(os, osname);
 
 	(void) printf("Dataset %s [%s], ID %llu, cr_txg %llu, "
 	    "%s, %llu objects%s%s\n",
 	    osname, type, (u_longlong_t)dmu_objset_id(os),
 	    (u_longlong_t)dds.dds_creation_txg,
 	    numbuf, (u_longlong_t)usedobjs, blkbuf,
 	    (dds.dds_inconsistent) ? " (inconsistent)" : "");
 
 	for (i = 0; i < zopt_object_args; i++) {
 		obj_start = zopt_object_ranges[i].zor_obj_start;
 		obj_end = zopt_object_ranges[i].zor_obj_end;
 		flags = zopt_object_ranges[i].zor_flags;
 
 		object = obj_start;
 		if (object == 0 || obj_start == obj_end)
 			dump_object(os, object, verbosity, &print_header, NULL,
 			    flags);
 		else
 			object--;
 
 		while ((dmu_object_next(os, &object, B_FALSE, 0) == 0) &&
 		    object <= obj_end) {
 			dump_object(os, object, verbosity, &print_header, NULL,
 			    flags);
 		}
 	}
 
 	if (zopt_object_args > 0) {
 		(void) printf("\n");
 		return;
 	}
 
 	if (dump_opt['i'] != 0 || verbosity >= 2)
 		dump_intent_log(dmu_objset_zil(os));
 
 	if (dmu_objset_ds(os) != NULL) {
 		dsl_dataset_t *ds = dmu_objset_ds(os);
 		dump_blkptr_list(&ds->ds_deadlist, "Deadlist");
 		if (dsl_deadlist_is_open(&ds->ds_dir->dd_livelist) &&
 		    !dmu_objset_is_snapshot(os)) {
 			dump_blkptr_list(&ds->ds_dir->dd_livelist, "Livelist");
 			if (verify_dd_livelist(os) != 0)
 				fatal("livelist is incorrect");
 		}
 
 		if (dsl_dataset_remap_deadlist_exists(ds)) {
 			(void) printf("ds_remap_deadlist:\n");
 			dump_blkptr_list(&ds->ds_remap_deadlist, "Deadlist");
 		}
 		count_ds_mos_objects(ds);
 	}
 
 	if (dmu_objset_ds(os) != NULL)
 		dump_bookmarks(os, verbosity);
 
 	if (verbosity < 2)
 		return;
 
 	if (BP_IS_HOLE(os->os_rootbp))
 		return;
 
 	dump_object(os, 0, verbosity, &print_header, NULL, 0);
 	object_count = 0;
 	if (DMU_USERUSED_DNODE(os) != NULL &&
 	    DMU_USERUSED_DNODE(os)->dn_type != 0) {
 		dump_object(os, DMU_USERUSED_OBJECT, verbosity, &print_header,
 		    NULL, 0);
 		dump_object(os, DMU_GROUPUSED_OBJECT, verbosity, &print_header,
 		    NULL, 0);
 	}
 
 	if (DMU_PROJECTUSED_DNODE(os) != NULL &&
 	    DMU_PROJECTUSED_DNODE(os)->dn_type != 0)
 		dump_object(os, DMU_PROJECTUSED_OBJECT, verbosity,
 		    &print_header, NULL, 0);
 
 	object = 0;
 	while ((error = dmu_object_next(os, &object, B_FALSE, 0)) == 0) {
 		dump_object(os, object, verbosity, &print_header, &dnode_slots,
 		    0);
 		object_count++;
 		total_slots_used += dnode_slots;
 		max_slot_used = object + dnode_slots - 1;
 	}
 
 	(void) printf("\n");
 
 	(void) printf("    Dnode slots:\n");
 	(void) printf("\tTotal used:    %10llu\n",
 	    (u_longlong_t)total_slots_used);
 	(void) printf("\tMax used:      %10llu\n",
 	    (u_longlong_t)max_slot_used);
 	(void) printf("\tPercent empty: %10lf\n",
 	    (double)(max_slot_used - total_slots_used)*100 /
 	    (double)max_slot_used);
 	(void) printf("\n");
 
 	if (error != ESRCH) {
 		(void) fprintf(stderr, "dmu_object_next() = %d\n", error);
 		abort();
 	}
 
 	ASSERT3U(object_count, ==, usedobjs);
 
 	if (leaked_objects != 0) {
 		(void) printf("%d potentially leaked objects detected\n",
 		    leaked_objects);
 		leaked_objects = 0;
 	}
 }
 
 static void
 dump_uberblock(uberblock_t *ub, const char *header, const char *footer)
 {
 	time_t timestamp = ub->ub_timestamp;
 
 	(void) printf("%s", header ? header : "");
 	(void) printf("\tmagic = %016llx\n", (u_longlong_t)ub->ub_magic);
 	(void) printf("\tversion = %llu\n", (u_longlong_t)ub->ub_version);
 	(void) printf("\ttxg = %llu\n", (u_longlong_t)ub->ub_txg);
 	(void) printf("\tguid_sum = %llu\n", (u_longlong_t)ub->ub_guid_sum);
 	(void) printf("\ttimestamp = %llu UTC = %s",
 	    (u_longlong_t)ub->ub_timestamp, ctime(&timestamp));
 
 	(void) printf("\tmmp_magic = %016llx\n",
 	    (u_longlong_t)ub->ub_mmp_magic);
 	if (MMP_VALID(ub)) {
 		(void) printf("\tmmp_delay = %0llu\n",
 		    (u_longlong_t)ub->ub_mmp_delay);
 		if (MMP_SEQ_VALID(ub))
 			(void) printf("\tmmp_seq = %u\n",
 			    (unsigned int) MMP_SEQ(ub));
 		if (MMP_FAIL_INT_VALID(ub))
 			(void) printf("\tmmp_fail = %u\n",
 			    (unsigned int) MMP_FAIL_INT(ub));
 		if (MMP_INTERVAL_VALID(ub))
 			(void) printf("\tmmp_write = %u\n",
 			    (unsigned int) MMP_INTERVAL(ub));
 		/* After MMP_* to make summarize_uberblock_mmp cleaner */
 		(void) printf("\tmmp_valid = %x\n",
 		    (unsigned int) ub->ub_mmp_config & 0xFF);
 	}
 
 	if (dump_opt['u'] >= 4) {
 		char blkbuf[BP_SPRINTF_LEN];
 		snprintf_blkptr(blkbuf, sizeof (blkbuf), &ub->ub_rootbp);
 		(void) printf("\trootbp = %s\n", blkbuf);
 	}
 	(void) printf("\tcheckpoint_txg = %llu\n",
 	    (u_longlong_t)ub->ub_checkpoint_txg);
 	(void) printf("%s", footer ? footer : "");
 }
 
 static void
 dump_config(spa_t *spa)
 {
 	dmu_buf_t *db;
 	size_t nvsize = 0;
 	int error = 0;
 
 
 	error = dmu_bonus_hold(spa->spa_meta_objset,
 	    spa->spa_config_object, FTAG, &db);
 
 	if (error == 0) {
 		nvsize = *(uint64_t *)db->db_data;
 		dmu_buf_rele(db, FTAG);
 
 		(void) printf("\nMOS Configuration:\n");
 		dump_packed_nvlist(spa->spa_meta_objset,
 		    spa->spa_config_object, (void *)&nvsize, 1);
 	} else {
 		(void) fprintf(stderr, "dmu_bonus_hold(%llu) failed, errno %d",
 		    (u_longlong_t)spa->spa_config_object, error);
 	}
 }
 
 static void
 dump_cachefile(const char *cachefile)
 {
 	int fd;
 	struct stat64 statbuf;
 	char *buf;
 	nvlist_t *config;
 
 	if ((fd = open64(cachefile, O_RDONLY)) < 0) {
 		(void) printf("cannot open '%s': %s\n", cachefile,
 		    strerror(errno));
 		exit(1);
 	}
 
 	if (fstat64(fd, &statbuf) != 0) {
 		(void) printf("failed to stat '%s': %s\n", cachefile,
 		    strerror(errno));
 		exit(1);
 	}
 
 	if ((buf = malloc(statbuf.st_size)) == NULL) {
 		(void) fprintf(stderr, "failed to allocate %llu bytes\n",
 		    (u_longlong_t)statbuf.st_size);
 		exit(1);
 	}
 
 	if (read(fd, buf, statbuf.st_size) != statbuf.st_size) {
 		(void) fprintf(stderr, "failed to read %llu bytes\n",
 		    (u_longlong_t)statbuf.st_size);
 		exit(1);
 	}
 
 	(void) close(fd);
 
 	if (nvlist_unpack(buf, statbuf.st_size, &config, 0) != 0) {
 		(void) fprintf(stderr, "failed to unpack nvlist\n");
 		exit(1);
 	}
 
 	free(buf);
 
 	dump_nvlist(config, 0);
 
 	nvlist_free(config);
 }
 
 /*
  * ZFS label nvlist stats
  */
 typedef struct zdb_nvl_stats {
 	int		zns_list_count;
 	int		zns_leaf_count;
 	size_t		zns_leaf_largest;
 	size_t		zns_leaf_total;
 	nvlist_t	*zns_string;
 	nvlist_t	*zns_uint64;
 	nvlist_t	*zns_boolean;
 } zdb_nvl_stats_t;
 
 static void
 collect_nvlist_stats(nvlist_t *nvl, zdb_nvl_stats_t *stats)
 {
 	nvlist_t *list, **array;
 	nvpair_t *nvp = NULL;
 	const char *name;
 	uint_t i, items;
 
 	stats->zns_list_count++;
 
 	while ((nvp = nvlist_next_nvpair(nvl, nvp)) != NULL) {
 		name = nvpair_name(nvp);
 
 		switch (nvpair_type(nvp)) {
 		case DATA_TYPE_STRING:
 			fnvlist_add_string(stats->zns_string, name,
 			    fnvpair_value_string(nvp));
 			break;
 		case DATA_TYPE_UINT64:
 			fnvlist_add_uint64(stats->zns_uint64, name,
 			    fnvpair_value_uint64(nvp));
 			break;
 		case DATA_TYPE_BOOLEAN:
 			fnvlist_add_boolean(stats->zns_boolean, name);
 			break;
 		case DATA_TYPE_NVLIST:
 			if (nvpair_value_nvlist(nvp, &list) == 0)
 				collect_nvlist_stats(list, stats);
 			break;
 		case DATA_TYPE_NVLIST_ARRAY:
 			if (nvpair_value_nvlist_array(nvp, &array, &items) != 0)
 				break;
 
 			for (i = 0; i < items; i++) {
 				collect_nvlist_stats(array[i], stats);
 
 				/* collect stats on leaf vdev */
 				if (strcmp(name, "children") == 0) {
 					size_t size;
 
 					(void) nvlist_size(array[i], &size,
 					    NV_ENCODE_XDR);
 					stats->zns_leaf_total += size;
 					if (size > stats->zns_leaf_largest)
 						stats->zns_leaf_largest = size;
 					stats->zns_leaf_count++;
 				}
 			}
 			break;
 		default:
 			(void) printf("skip type %d!\n", (int)nvpair_type(nvp));
 		}
 	}
 }
 
 static void
 dump_nvlist_stats(nvlist_t *nvl, size_t cap)
 {
 	zdb_nvl_stats_t stats = { 0 };
 	size_t size, sum = 0, total;
 	size_t noise;
 
 	/* requires nvlist with non-unique names for stat collection */
 	VERIFY0(nvlist_alloc(&stats.zns_string, 0, 0));
 	VERIFY0(nvlist_alloc(&stats.zns_uint64, 0, 0));
 	VERIFY0(nvlist_alloc(&stats.zns_boolean, 0, 0));
 	VERIFY0(nvlist_size(stats.zns_boolean, &noise, NV_ENCODE_XDR));
 
 	(void) printf("\n\nZFS Label NVList Config Stats:\n");
 
 	VERIFY0(nvlist_size(nvl, &total, NV_ENCODE_XDR));
 	(void) printf("  %d bytes used, %d bytes free (using %4.1f%%)\n\n",
 	    (int)total, (int)(cap - total), 100.0 * total / cap);
 
 	collect_nvlist_stats(nvl, &stats);
 
 	VERIFY0(nvlist_size(stats.zns_uint64, &size, NV_ENCODE_XDR));
 	size -= noise;
 	sum += size;
 	(void) printf("%12s %4d %6d bytes (%5.2f%%)\n", "integers:",
 	    (int)fnvlist_num_pairs(stats.zns_uint64),
 	    (int)size, 100.0 * size / total);
 
 	VERIFY0(nvlist_size(stats.zns_string, &size, NV_ENCODE_XDR));
 	size -= noise;
 	sum += size;
 	(void) printf("%12s %4d %6d bytes (%5.2f%%)\n", "strings:",
 	    (int)fnvlist_num_pairs(stats.zns_string),
 	    (int)size, 100.0 * size / total);
 
 	VERIFY0(nvlist_size(stats.zns_boolean, &size, NV_ENCODE_XDR));
 	size -= noise;
 	sum += size;
 	(void) printf("%12s %4d %6d bytes (%5.2f%%)\n", "booleans:",
 	    (int)fnvlist_num_pairs(stats.zns_boolean),
 	    (int)size, 100.0 * size / total);
 
 	size = total - sum;	/* treat remainder as nvlist overhead */
 	(void) printf("%12s %4d %6d bytes (%5.2f%%)\n\n", "nvlists:",
 	    stats.zns_list_count, (int)size, 100.0 * size / total);
 
 	if (stats.zns_leaf_count > 0) {
 		size_t average = stats.zns_leaf_total / stats.zns_leaf_count;
 
 		(void) printf("%12s %4d %6d bytes average\n", "leaf vdevs:",
 		    stats.zns_leaf_count, (int)average);
 		(void) printf("%24d bytes largest\n",
 		    (int)stats.zns_leaf_largest);
 
 		if (dump_opt['l'] >= 3 && average > 0)
 			(void) printf("  space for %d additional leaf vdevs\n",
 			    (int)((cap - total) / average));
 	}
 	(void) printf("\n");
 
 	nvlist_free(stats.zns_string);
 	nvlist_free(stats.zns_uint64);
 	nvlist_free(stats.zns_boolean);
 }
 
 typedef struct cksum_record {
 	zio_cksum_t cksum;
 	boolean_t labels[VDEV_LABELS];
 	avl_node_t link;
 } cksum_record_t;
 
 static int
 cksum_record_compare(const void *x1, const void *x2)
 {
 	const cksum_record_t *l = (cksum_record_t *)x1;
 	const cksum_record_t *r = (cksum_record_t *)x2;
 	int arraysize = ARRAY_SIZE(l->cksum.zc_word);
 	int difference = 0;
 
 	for (int i = 0; i < arraysize; i++) {
 		difference = TREE_CMP(l->cksum.zc_word[i], r->cksum.zc_word[i]);
 		if (difference)
 			break;
 	}
 
 	return (difference);
 }
 
 static cksum_record_t *
 cksum_record_alloc(zio_cksum_t *cksum, int l)
 {
 	cksum_record_t *rec;
 
 	rec = umem_zalloc(sizeof (*rec), UMEM_NOFAIL);
 	rec->cksum = *cksum;
 	rec->labels[l] = B_TRUE;
 
 	return (rec);
 }
 
 static cksum_record_t *
 cksum_record_lookup(avl_tree_t *tree, zio_cksum_t *cksum)
 {
 	cksum_record_t lookup = { .cksum = *cksum };
 	avl_index_t where;
 
 	return (avl_find(tree, &lookup, &where));
 }
 
 static cksum_record_t *
 cksum_record_insert(avl_tree_t *tree, zio_cksum_t *cksum, int l)
 {
 	cksum_record_t *rec;
 
 	rec = cksum_record_lookup(tree, cksum);
 	if (rec) {
 		rec->labels[l] = B_TRUE;
 	} else {
 		rec = cksum_record_alloc(cksum, l);
 		avl_add(tree, rec);
 	}
 
 	return (rec);
 }
 
 static int
 first_label(cksum_record_t *rec)
 {
 	for (int i = 0; i < VDEV_LABELS; i++)
 		if (rec->labels[i])
 			return (i);
 
 	return (-1);
 }
 
 static void
 print_label_numbers(const char *prefix, const cksum_record_t *rec)
 {
 	fputs(prefix, stdout);
 	for (int i = 0; i < VDEV_LABELS; i++)
 		if (rec->labels[i] == B_TRUE)
 			printf("%d ", i);
 	putchar('\n');
 }
 
 #define	MAX_UBERBLOCK_COUNT (VDEV_UBERBLOCK_RING >> UBERBLOCK_SHIFT)
 
 typedef struct zdb_label {
 	vdev_label_t label;
 	uint64_t label_offset;
 	nvlist_t *config_nv;
 	cksum_record_t *config;
 	cksum_record_t *uberblocks[MAX_UBERBLOCK_COUNT];
 	boolean_t header_printed;
 	boolean_t read_failed;
 	boolean_t cksum_valid;
 } zdb_label_t;
 
 static void
 print_label_header(zdb_label_t *label, int l)
 {
 
 	if (dump_opt['q'])
 		return;
 
 	if (label->header_printed == B_TRUE)
 		return;
 
 	(void) printf("------------------------------------\n");
 	(void) printf("LABEL %d %s\n", l,
 	    label->cksum_valid ? "" : "(Bad label cksum)");
 	(void) printf("------------------------------------\n");
 
 	label->header_printed = B_TRUE;
 }
 
 static void
 print_l2arc_header(void)
 {
 	(void) printf("------------------------------------\n");
 	(void) printf("L2ARC device header\n");
 	(void) printf("------------------------------------\n");
 }
 
 static void
 print_l2arc_log_blocks(void)
 {
 	(void) printf("------------------------------------\n");
 	(void) printf("L2ARC device log blocks\n");
 	(void) printf("------------------------------------\n");
 }
 
 static void
 dump_l2arc_log_entries(uint64_t log_entries,
     l2arc_log_ent_phys_t *le, uint64_t i)
 {
 	for (int j = 0; j < log_entries; j++) {
 		dva_t dva = le[j].le_dva;
 		(void) printf("lb[%4llu]\tle[%4d]\tDVA asize: %llu, "
 		    "vdev: %llu, offset: %llu\n",
 		    (u_longlong_t)i, j + 1,
 		    (u_longlong_t)DVA_GET_ASIZE(&dva),
 		    (u_longlong_t)DVA_GET_VDEV(&dva),
 		    (u_longlong_t)DVA_GET_OFFSET(&dva));
 		(void) printf("|\t\t\t\tbirth: %llu\n",
 		    (u_longlong_t)le[j].le_birth);
 		(void) printf("|\t\t\t\tlsize: %llu\n",
 		    (u_longlong_t)L2BLK_GET_LSIZE((&le[j])->le_prop));
 		(void) printf("|\t\t\t\tpsize: %llu\n",
 		    (u_longlong_t)L2BLK_GET_PSIZE((&le[j])->le_prop));
 		(void) printf("|\t\t\t\tcompr: %llu\n",
 		    (u_longlong_t)L2BLK_GET_COMPRESS((&le[j])->le_prop));
 		(void) printf("|\t\t\t\tcomplevel: %llu\n",
 		    (u_longlong_t)(&le[j])->le_complevel);
 		(void) printf("|\t\t\t\ttype: %llu\n",
 		    (u_longlong_t)L2BLK_GET_TYPE((&le[j])->le_prop));
 		(void) printf("|\t\t\t\tprotected: %llu\n",
 		    (u_longlong_t)L2BLK_GET_PROTECTED((&le[j])->le_prop));
 		(void) printf("|\t\t\t\tprefetch: %llu\n",
 		    (u_longlong_t)L2BLK_GET_PREFETCH((&le[j])->le_prop));
 		(void) printf("|\t\t\t\taddress: %llu\n",
 		    (u_longlong_t)le[j].le_daddr);
 		(void) printf("|\t\t\t\tARC state: %llu\n",
 		    (u_longlong_t)L2BLK_GET_STATE((&le[j])->le_prop));
 		(void) printf("|\n");
 	}
 	(void) printf("\n");
 }
 
 static void
 dump_l2arc_log_blkptr(const l2arc_log_blkptr_t *lbps)
 {
 	(void) printf("|\t\tdaddr: %llu\n", (u_longlong_t)lbps->lbp_daddr);
 	(void) printf("|\t\tpayload_asize: %llu\n",
 	    (u_longlong_t)lbps->lbp_payload_asize);
 	(void) printf("|\t\tpayload_start: %llu\n",
 	    (u_longlong_t)lbps->lbp_payload_start);
 	(void) printf("|\t\tlsize: %llu\n",
 	    (u_longlong_t)L2BLK_GET_LSIZE(lbps->lbp_prop));
 	(void) printf("|\t\tasize: %llu\n",
 	    (u_longlong_t)L2BLK_GET_PSIZE(lbps->lbp_prop));
 	(void) printf("|\t\tcompralgo: %llu\n",
 	    (u_longlong_t)L2BLK_GET_COMPRESS(lbps->lbp_prop));
 	(void) printf("|\t\tcksumalgo: %llu\n",
 	    (u_longlong_t)L2BLK_GET_CHECKSUM(lbps->lbp_prop));
 	(void) printf("|\n\n");
 }
 
 static void
 dump_l2arc_log_blocks(int fd, const l2arc_dev_hdr_phys_t *l2dhdr,
     l2arc_dev_hdr_phys_t *rebuild)
 {
 	l2arc_log_blk_phys_t this_lb;
 	uint64_t asize;
 	l2arc_log_blkptr_t lbps[2];
 	abd_t *abd;
 	zio_cksum_t cksum;
 	int failed = 0;
 	l2arc_dev_t dev;
 
 	if (!dump_opt['q'])
 		print_l2arc_log_blocks();
 	memcpy(lbps, l2dhdr->dh_start_lbps, sizeof (lbps));
 
 	dev.l2ad_evict = l2dhdr->dh_evict;
 	dev.l2ad_start = l2dhdr->dh_start;
 	dev.l2ad_end = l2dhdr->dh_end;
 
 	if (l2dhdr->dh_start_lbps[0].lbp_daddr == 0) {
 		/* no log blocks to read */
 		if (!dump_opt['q']) {
 			(void) printf("No log blocks to read\n");
 			(void) printf("\n");
 		}
 		return;
 	} else {
 		dev.l2ad_hand = lbps[0].lbp_daddr +
 		    L2BLK_GET_PSIZE((&lbps[0])->lbp_prop);
 	}
 
 	dev.l2ad_first = !!(l2dhdr->dh_flags & L2ARC_DEV_HDR_EVICT_FIRST);
 
 	for (;;) {
 		if (!l2arc_log_blkptr_valid(&dev, &lbps[0]))
 			break;
 
 		/* L2BLK_GET_PSIZE returns aligned size for log blocks */
 		asize = L2BLK_GET_PSIZE((&lbps[0])->lbp_prop);
 		if (pread64(fd, &this_lb, asize, lbps[0].lbp_daddr) != asize) {
 			if (!dump_opt['q']) {
 				(void) printf("Error while reading next log "
 				    "block\n\n");
 			}
 			break;
 		}
 
 		fletcher_4_native_varsize(&this_lb, asize, &cksum);
 		if (!ZIO_CHECKSUM_EQUAL(cksum, lbps[0].lbp_cksum)) {
 			failed++;
 			if (!dump_opt['q']) {
 				(void) printf("Invalid cksum\n");
 				dump_l2arc_log_blkptr(&lbps[0]);
 			}
 			break;
 		}
 
 		switch (L2BLK_GET_COMPRESS((&lbps[0])->lbp_prop)) {
 		case ZIO_COMPRESS_OFF:
 			break;
 		default:
 			abd = abd_alloc_for_io(asize, B_TRUE);
 			abd_copy_from_buf_off(abd, &this_lb, 0, asize);
 			if (zio_decompress_data(L2BLK_GET_COMPRESS(
 			    (&lbps[0])->lbp_prop), abd, &this_lb,
 			    asize, sizeof (this_lb), NULL) != 0) {
 				(void) printf("L2ARC block decompression "
 				    "failed\n");
 				abd_free(abd);
 				goto out;
 			}
 			abd_free(abd);
 			break;
 		}
 
 		if (this_lb.lb_magic == BSWAP_64(L2ARC_LOG_BLK_MAGIC))
 			byteswap_uint64_array(&this_lb, sizeof (this_lb));
 		if (this_lb.lb_magic != L2ARC_LOG_BLK_MAGIC) {
 			if (!dump_opt['q'])
 				(void) printf("Invalid log block magic\n\n");
 			break;
 		}
 
 		rebuild->dh_lb_count++;
 		rebuild->dh_lb_asize += asize;
 		if (dump_opt['l'] > 1 && !dump_opt['q']) {
 			(void) printf("lb[%4llu]\tmagic: %llu\n",
 			    (u_longlong_t)rebuild->dh_lb_count,
 			    (u_longlong_t)this_lb.lb_magic);
 			dump_l2arc_log_blkptr(&lbps[0]);
 		}
 
 		if (dump_opt['l'] > 2 && !dump_opt['q'])
 			dump_l2arc_log_entries(l2dhdr->dh_log_entries,
 			    this_lb.lb_entries,
 			    rebuild->dh_lb_count);
 
 		if (l2arc_range_check_overlap(lbps[1].lbp_payload_start,
 		    lbps[0].lbp_payload_start, dev.l2ad_evict) &&
 		    !dev.l2ad_first)
 			break;
 
 		lbps[0] = lbps[1];
 		lbps[1] = this_lb.lb_prev_lbp;
 	}
 out:
 	if (!dump_opt['q']) {
 		(void) printf("log_blk_count:\t %llu with valid cksum\n",
 		    (u_longlong_t)rebuild->dh_lb_count);
 		(void) printf("\t\t %d with invalid cksum\n", failed);
 		(void) printf("log_blk_asize:\t %llu\n\n",
 		    (u_longlong_t)rebuild->dh_lb_asize);
 	}
 }
 
 static int
 dump_l2arc_header(int fd)
 {
 	l2arc_dev_hdr_phys_t l2dhdr = {0}, rebuild = {0};
 	int error = B_FALSE;
 
 	if (pread64(fd, &l2dhdr, sizeof (l2dhdr),
 	    VDEV_LABEL_START_SIZE) != sizeof (l2dhdr)) {
 		error = B_TRUE;
 	} else {
 		if (l2dhdr.dh_magic == BSWAP_64(L2ARC_DEV_HDR_MAGIC))
 			byteswap_uint64_array(&l2dhdr, sizeof (l2dhdr));
 
 		if (l2dhdr.dh_magic != L2ARC_DEV_HDR_MAGIC)
 			error = B_TRUE;
 	}
 
 	if (error) {
 		(void) printf("L2ARC device header not found\n\n");
 		/* Do not return an error here for backward compatibility */
 		return (0);
 	} else if (!dump_opt['q']) {
 		print_l2arc_header();
 
 		(void) printf("    magic: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_magic);
 		(void) printf("    version: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_version);
 		(void) printf("    pool_guid: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_spa_guid);
 		(void) printf("    flags: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_flags);
 		(void) printf("    start_lbps[0]: %llu\n",
 		    (u_longlong_t)
 		    l2dhdr.dh_start_lbps[0].lbp_daddr);
 		(void) printf("    start_lbps[1]: %llu\n",
 		    (u_longlong_t)
 		    l2dhdr.dh_start_lbps[1].lbp_daddr);
 		(void) printf("    log_blk_ent: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_log_entries);
 		(void) printf("    start: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_start);
 		(void) printf("    end: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_end);
 		(void) printf("    evict: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_evict);
 		(void) printf("    lb_asize_refcount: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_lb_asize);
 		(void) printf("    lb_count_refcount: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_lb_count);
 		(void) printf("    trim_action_time: %llu\n",
 		    (u_longlong_t)l2dhdr.dh_trim_action_time);
 		(void) printf("    trim_state: %llu\n\n",
 		    (u_longlong_t)l2dhdr.dh_trim_state);
 	}
 
 	dump_l2arc_log_blocks(fd, &l2dhdr, &rebuild);
 	/*
 	 * The total aligned size of log blocks and the number of log blocks
 	 * reported in the header of the device may be less than what zdb
 	 * reports by dump_l2arc_log_blocks() which emulates l2arc_rebuild().
 	 * This happens because dump_l2arc_log_blocks() lacks the memory
 	 * pressure valve that l2arc_rebuild() has. Thus, if we are on a system
 	 * with low memory, l2arc_rebuild will exit prematurely and dh_lb_asize
 	 * and dh_lb_count will be lower to begin with than what exists on the
 	 * device. This is normal and zdb should not exit with an error. The
 	 * opposite case should never happen though, the values reported in the
 	 * header should never be higher than what dump_l2arc_log_blocks() and
 	 * l2arc_rebuild() report. If this happens there is a leak in the
 	 * accounting of log blocks.
 	 */
 	if (l2dhdr.dh_lb_asize > rebuild.dh_lb_asize ||
 	    l2dhdr.dh_lb_count > rebuild.dh_lb_count)
 		return (1);
 
 	return (0);
 }
 
 static void
 dump_config_from_label(zdb_label_t *label, size_t buflen, int l)
 {
 	if (dump_opt['q'])
 		return;
 
 	if ((dump_opt['l'] < 3) && (first_label(label->config) != l))
 		return;
 
 	print_label_header(label, l);
 	dump_nvlist(label->config_nv, 4);
 	print_label_numbers("    labels = ", label->config);
 
 	if (dump_opt['l'] >= 2)
 		dump_nvlist_stats(label->config_nv, buflen);
 }
 
 #define	ZDB_MAX_UB_HEADER_SIZE 32
 
 static void
 dump_label_uberblocks(zdb_label_t *label, uint64_t ashift, int label_num)
 {
 
 	vdev_t vd;
 	char header[ZDB_MAX_UB_HEADER_SIZE];
 
 	vd.vdev_ashift = ashift;
 	vd.vdev_top = &vd;
 
 	for (int i = 0; i < VDEV_UBERBLOCK_COUNT(&vd); i++) {
 		uint64_t uoff = VDEV_UBERBLOCK_OFFSET(&vd, i);
 		uberblock_t *ub = (void *)((char *)&label->label + uoff);
 		cksum_record_t *rec = label->uberblocks[i];
 
 		if (rec == NULL) {
 			if (dump_opt['u'] >= 2) {
 				print_label_header(label, label_num);
 				(void) printf("    Uberblock[%d] invalid\n", i);
 			}
 			continue;
 		}
 
 		if ((dump_opt['u'] < 3) && (first_label(rec) != label_num))
 			continue;
 
 		if ((dump_opt['u'] < 4) &&
 		    (ub->ub_mmp_magic == MMP_MAGIC) && ub->ub_mmp_delay &&
 		    (i >= VDEV_UBERBLOCK_COUNT(&vd) - MMP_BLOCKS_PER_LABEL))
 			continue;
 
 		print_label_header(label, label_num);
 		(void) snprintf(header, ZDB_MAX_UB_HEADER_SIZE,
 		    "    Uberblock[%d]\n", i);
 		dump_uberblock(ub, header, "");
 		print_label_numbers("        labels = ", rec);
 	}
 }
 
 static char curpath[PATH_MAX];
 
 /*
  * Iterate through the path components, recursively passing
  * current one's obj and remaining path until we find the obj
  * for the last one.
  */
 static int
 dump_path_impl(objset_t *os, uint64_t obj, char *name, uint64_t *retobj)
 {
 	int err;
 	boolean_t header = B_TRUE;
 	uint64_t child_obj;
 	char *s;
 	dmu_buf_t *db;
 	dmu_object_info_t doi;
 
 	if ((s = strchr(name, '/')) != NULL)
 		*s = '\0';
 	err = zap_lookup(os, obj, name, 8, 1, &child_obj);
 
 	(void) strlcat(curpath, name, sizeof (curpath));
 
 	if (err != 0) {
 		(void) fprintf(stderr, "failed to lookup %s: %s\n",
 		    curpath, strerror(err));
 		return (err);
 	}
 
 	child_obj = ZFS_DIRENT_OBJ(child_obj);
 	err = sa_buf_hold(os, child_obj, FTAG, &db);
 	if (err != 0) {
 		(void) fprintf(stderr,
 		    "failed to get SA dbuf for obj %llu: %s\n",
 		    (u_longlong_t)child_obj, strerror(err));
 		return (EINVAL);
 	}
 	dmu_object_info_from_db(db, &doi);
 	sa_buf_rele(db, FTAG);
 
 	if (doi.doi_bonus_type != DMU_OT_SA &&
 	    doi.doi_bonus_type != DMU_OT_ZNODE) {
 		(void) fprintf(stderr, "invalid bonus type %d for obj %llu\n",
 		    doi.doi_bonus_type, (u_longlong_t)child_obj);
 		return (EINVAL);
 	}
 
 	if (dump_opt['v'] > 6) {
 		(void) printf("obj=%llu %s type=%d bonustype=%d\n",
 		    (u_longlong_t)child_obj, curpath, doi.doi_type,
 		    doi.doi_bonus_type);
 	}
 
 	(void) strlcat(curpath, "/", sizeof (curpath));
 
 	switch (doi.doi_type) {
 	case DMU_OT_DIRECTORY_CONTENTS:
 		if (s != NULL && *(s + 1) != '\0')
 			return (dump_path_impl(os, child_obj, s + 1, retobj));
 		zfs_fallthrough;
 	case DMU_OT_PLAIN_FILE_CONTENTS:
 		if (retobj != NULL) {
 			*retobj = child_obj;
 		} else {
 			dump_object(os, child_obj, dump_opt['v'], &header,
 			    NULL, 0);
 		}
 		return (0);
 	default:
 		(void) fprintf(stderr, "object %llu has non-file/directory "
 		    "type %d\n", (u_longlong_t)obj, doi.doi_type);
 		break;
 	}
 
 	return (EINVAL);
 }
 
 /*
  * Dump the blocks for the object specified by path inside the dataset.
  */
 static int
 dump_path(char *ds, char *path, uint64_t *retobj)
 {
 	int err;
 	objset_t *os;
 	uint64_t root_obj;
 
 	err = open_objset(ds, FTAG, &os);
 	if (err != 0)
 		return (err);
 
 	err = zap_lookup(os, MASTER_NODE_OBJ, ZFS_ROOT_OBJ, 8, 1, &root_obj);
 	if (err != 0) {
 		(void) fprintf(stderr, "can't lookup root znode: %s\n",
 		    strerror(err));
 		close_objset(os, FTAG);
 		return (EINVAL);
 	}
 
 	(void) snprintf(curpath, sizeof (curpath), "dataset=%s path=/", ds);
 
 	err = dump_path_impl(os, root_obj, path, retobj);
 
 	close_objset(os, FTAG);
 	return (err);
 }
 
 static int
 dump_backup_bytes(objset_t *os, void *buf, int len, void *arg)
 {
 	const char *p = (const char *)buf;
 	ssize_t nwritten;
 
 	(void) os;
 	(void) arg;
 
 	/* Write the data out, handling short writes and signals. */
 	while ((nwritten = write(STDOUT_FILENO, p, len)) < len) {
 		if (nwritten < 0) {
 			if (errno == EINTR)
 				continue;
 			return (errno);
 		}
 		p += nwritten;
 		len -= nwritten;
 	}
 
 	return (0);
 }
 
 static void
 dump_backup(const char *pool, uint64_t objset_id, const char *flagstr)
 {
 	boolean_t embed = B_FALSE;
 	boolean_t large_block = B_FALSE;
 	boolean_t compress = B_FALSE;
 	boolean_t raw = B_FALSE;
 
 	const char *c;
 	for (c = flagstr; c != NULL && *c != '\0'; c++) {
 		switch (*c) {
 			case 'e':
 				embed = B_TRUE;
 				break;
 			case 'L':
 				large_block = B_TRUE;
 				break;
 			case 'c':
 				compress = B_TRUE;
 				break;
 			case 'w':
 				raw = B_TRUE;
 				break;
 			default:
 				fprintf(stderr, "dump_backup: invalid flag "
 				    "'%c'\n", *c);
 				return;
 		}
 	}
 
 	if (isatty(STDOUT_FILENO)) {
 		fprintf(stderr, "dump_backup: stream cannot be written "
 		    "to a terminal\n");
 		return;
 	}
 
 	offset_t off = 0;
 	dmu_send_outparams_t out = {
 	    .dso_outfunc = dump_backup_bytes,
 	    .dso_dryrun  = B_FALSE,
 	};
 
 	int err = dmu_send_obj(pool, objset_id, /* fromsnap */0, embed,
 	    large_block, compress, raw, /* saved */ B_FALSE, STDOUT_FILENO,
 	    &off, &out);
 	if (err != 0) {
 		fprintf(stderr, "dump_backup: dmu_send_obj: %s\n",
 		    strerror(err));
 		return;
 	}
 }
 
 static int
 zdb_copy_object(objset_t *os, uint64_t srcobj, char *destfile)
 {
 	int err = 0;
 	uint64_t size, readsize, oursize, offset;
 	ssize_t writesize;
 	sa_handle_t *hdl;
 
 	(void) printf("Copying object %" PRIu64 " to file %s\n", srcobj,
 	    destfile);
 
 	VERIFY3P(os, ==, sa_os);
 	if ((err = sa_handle_get(os, srcobj, NULL, SA_HDL_PRIVATE, &hdl))) {
 		(void) printf("Failed to get handle for SA znode\n");
 		return (err);
 	}
 	if ((err = sa_lookup(hdl, sa_attr_table[ZPL_SIZE], &size, 8))) {
 		(void) sa_handle_destroy(hdl);
 		return (err);
 	}
 	(void) sa_handle_destroy(hdl);
 
 	(void) printf("Object %" PRIu64 " is %" PRIu64 " bytes\n", srcobj,
 	    size);
 	if (size == 0) {
 		return (EINVAL);
 	}
 
 	int fd = open(destfile, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 	if (fd == -1)
 		return (errno);
 	/*
 	 * We cap the size at 1 mebibyte here to prevent
 	 * allocation failures and nigh-infinite printing if the
 	 * object is extremely large.
 	 */
 	oursize = MIN(size, 1 << 20);
 	offset = 0;
 	char *buf = kmem_alloc(oursize, KM_NOSLEEP);
 	if (buf == NULL) {
 		(void) close(fd);
 		return (ENOMEM);
 	}
 
 	while (offset < size) {
 		readsize = MIN(size - offset, 1 << 20);
 		err = dmu_read(os, srcobj, offset, readsize, buf, 0);
 		if (err != 0) {
 			(void) printf("got error %u from dmu_read\n", err);
 			kmem_free(buf, oursize);
 			(void) close(fd);
 			return (err);
 		}
 		if (dump_opt['v'] > 3) {
 			(void) printf("Read offset=%" PRIu64 " size=%" PRIu64
 			    " error=%d\n", offset, readsize, err);
 		}
 
 		writesize = write(fd, buf, readsize);
 		if (writesize < 0) {
 			err = errno;
 			break;
 		} else if (writesize != readsize) {
 			/* Incomplete write */
 			(void) fprintf(stderr, "Short write, only wrote %llu of"
 			    " %" PRIu64 " bytes, exiting...\n",
 			    (u_longlong_t)writesize, readsize);
 			break;
 		}
 
 		offset += readsize;
 	}
 
 	(void) close(fd);
 
 	if (buf != NULL)
 		kmem_free(buf, oursize);
 
 	return (err);
 }
 
 static boolean_t
 label_cksum_valid(vdev_label_t *label, uint64_t offset)
 {
 	zio_checksum_info_t *ci = &zio_checksum_table[ZIO_CHECKSUM_LABEL];
 	zio_cksum_t expected_cksum;
 	zio_cksum_t actual_cksum;
 	zio_cksum_t verifier;
 	zio_eck_t *eck;
 	int byteswap;
 
 	void *data = (char *)label + offsetof(vdev_label_t, vl_vdev_phys);
 	eck = (zio_eck_t *)((char *)(data) + VDEV_PHYS_SIZE) - 1;
 
 	offset += offsetof(vdev_label_t, vl_vdev_phys);
 	ZIO_SET_CHECKSUM(&verifier, offset, 0, 0, 0);
 
 	byteswap = (eck->zec_magic == BSWAP_64(ZEC_MAGIC));
 	if (byteswap)
 		byteswap_uint64_array(&verifier, sizeof (zio_cksum_t));
 
 	expected_cksum = eck->zec_cksum;
 	eck->zec_cksum = verifier;
 
 	abd_t *abd = abd_get_from_buf(data, VDEV_PHYS_SIZE);
 	ci->ci_func[byteswap](abd, VDEV_PHYS_SIZE, NULL, &actual_cksum);
 	abd_free(abd);
 
 	if (byteswap)
 		byteswap_uint64_array(&expected_cksum, sizeof (zio_cksum_t));
 
 	if (ZIO_CHECKSUM_EQUAL(actual_cksum, expected_cksum))
 		return (B_TRUE);
 
 	return (B_FALSE);
 }
 
 static int
 dump_label(const char *dev)
 {
 	char path[MAXPATHLEN];
 	zdb_label_t labels[VDEV_LABELS] = {{{{0}}}};
 	uint64_t psize, ashift, l2cache;
 	struct stat64 statbuf;
 	boolean_t config_found = B_FALSE;
 	boolean_t error = B_FALSE;
 	boolean_t read_l2arc_header = B_FALSE;
 	avl_tree_t config_tree;
 	avl_tree_t uberblock_tree;
 	void *node, *cookie;
 	int fd;
 
 	/*
 	 * Check if we were given absolute path and use it as is.
 	 * Otherwise if the provided vdev name doesn't point to a file,
 	 * try prepending expected disk paths and partition numbers.
 	 */
 	(void) strlcpy(path, dev, sizeof (path));
 	if (dev[0] != '/' && stat64(path, &statbuf) != 0) {
 		int error;
 
 		error = zfs_resolve_shortname(dev, path, MAXPATHLEN);
 		if (error == 0 && zfs_dev_is_whole_disk(path)) {
 			if (zfs_append_partition(path, MAXPATHLEN) == -1)
 				error = ENOENT;
 		}
 
 		if (error || (stat64(path, &statbuf) != 0)) {
 			(void) printf("failed to find device %s, try "
 			    "specifying absolute path instead\n", dev);
 			return (1);
 		}
 	}
 
 	if ((fd = open64(path, O_RDONLY)) < 0) {
 		(void) printf("cannot open '%s': %s\n", path, strerror(errno));
 		exit(1);
 	}
 
 	if (fstat64_blk(fd, &statbuf) != 0) {
 		(void) printf("failed to stat '%s': %s\n", path,
 		    strerror(errno));
 		(void) close(fd);
 		exit(1);
 	}
 
 	if (S_ISBLK(statbuf.st_mode) && zfs_dev_flush(fd) != 0)
 		(void) printf("failed to invalidate cache '%s' : %s\n", path,
 		    strerror(errno));
 
 	avl_create(&config_tree, cksum_record_compare,
 	    sizeof (cksum_record_t), offsetof(cksum_record_t, link));
 	avl_create(&uberblock_tree, cksum_record_compare,
 	    sizeof (cksum_record_t), offsetof(cksum_record_t, link));
 
 	psize = statbuf.st_size;
 	psize = P2ALIGN_TYPED(psize, sizeof (vdev_label_t), uint64_t);
 	ashift = SPA_MINBLOCKSHIFT;
 
 	/*
 	 * 1. Read the label from disk
 	 * 2. Verify label cksum
 	 * 3. Unpack the configuration and insert in config tree.
 	 * 4. Traverse all uberblocks and insert in uberblock tree.
 	 */
 	for (int l = 0; l < VDEV_LABELS; l++) {
 		zdb_label_t *label = &labels[l];
 		char *buf = label->label.vl_vdev_phys.vp_nvlist;
 		size_t buflen = sizeof (label->label.vl_vdev_phys.vp_nvlist);
 		nvlist_t *config;
 		cksum_record_t *rec;
 		zio_cksum_t cksum;
 		vdev_t vd;
 
 		label->label_offset = vdev_label_offset(psize, l, 0);
 
 		if (pread64(fd, &label->label, sizeof (label->label),
 		    label->label_offset) != sizeof (label->label)) {
 			if (!dump_opt['q'])
 				(void) printf("failed to read label %d\n", l);
 			label->read_failed = B_TRUE;
 			error = B_TRUE;
 			continue;
 		}
 
 		label->read_failed = B_FALSE;
 		label->cksum_valid = label_cksum_valid(&label->label,
 		    label->label_offset);
 
 		if (nvlist_unpack(buf, buflen, &config, 0) == 0) {
 			nvlist_t *vdev_tree = NULL;
 			size_t size;
 
 			if ((nvlist_lookup_nvlist(config,
 			    ZPOOL_CONFIG_VDEV_TREE, &vdev_tree) != 0) ||
 			    (nvlist_lookup_uint64(vdev_tree,
 			    ZPOOL_CONFIG_ASHIFT, &ashift) != 0))
 				ashift = SPA_MINBLOCKSHIFT;
 
 			if (nvlist_size(config, &size, NV_ENCODE_XDR) != 0)
 				size = buflen;
 
 			/* If the device is a cache device read the header. */
 			if (!read_l2arc_header) {
 				if (nvlist_lookup_uint64(config,
 				    ZPOOL_CONFIG_POOL_STATE, &l2cache) == 0 &&
 				    l2cache == POOL_STATE_L2CACHE) {
 					read_l2arc_header = B_TRUE;
 				}
 			}
 
 			fletcher_4_native_varsize(buf, size, &cksum);
 			rec = cksum_record_insert(&config_tree, &cksum, l);
 
 			label->config = rec;
 			label->config_nv = config;
 			config_found = B_TRUE;
 		} else {
 			error = B_TRUE;
 		}
 
 		vd.vdev_ashift = ashift;
 		vd.vdev_top = &vd;
 
 		for (int i = 0; i < VDEV_UBERBLOCK_COUNT(&vd); i++) {
 			uint64_t uoff = VDEV_UBERBLOCK_OFFSET(&vd, i);
 			uberblock_t *ub = (void *)((char *)label + uoff);
 
 			if (uberblock_verify(ub))
 				continue;
 
 			fletcher_4_native_varsize(ub, sizeof (*ub), &cksum);
 			rec = cksum_record_insert(&uberblock_tree, &cksum, l);
 
 			label->uberblocks[i] = rec;
 		}
 	}
 
 	/*
 	 * Dump the label and uberblocks.
 	 */
 	for (int l = 0; l < VDEV_LABELS; l++) {
 		zdb_label_t *label = &labels[l];
 		size_t buflen = sizeof (label->label.vl_vdev_phys.vp_nvlist);
 
 		if (label->read_failed == B_TRUE)
 			continue;
 
 		if (label->config_nv) {
 			dump_config_from_label(label, buflen, l);
 		} else {
 			if (!dump_opt['q'])
 				(void) printf("failed to unpack label %d\n", l);
 		}
 
 		if (dump_opt['u'])
 			dump_label_uberblocks(label, ashift, l);
 
 		nvlist_free(label->config_nv);
 	}
 
 	/*
 	 * Dump the L2ARC header, if existent.
 	 */
 	if (read_l2arc_header)
 		error |= dump_l2arc_header(fd);
 
 	cookie = NULL;
 	while ((node = avl_destroy_nodes(&config_tree, &cookie)) != NULL)
 		umem_free(node, sizeof (cksum_record_t));
 
 	cookie = NULL;
 	while ((node = avl_destroy_nodes(&uberblock_tree, &cookie)) != NULL)
 		umem_free(node, sizeof (cksum_record_t));
 
 	avl_destroy(&config_tree);
 	avl_destroy(&uberblock_tree);
 
 	(void) close(fd);
 
 	return (config_found == B_FALSE ? 2 :
 	    (error == B_TRUE ? 1 : 0));
 }
 
 static uint64_t dataset_feature_count[SPA_FEATURES];
 static uint64_t global_feature_count[SPA_FEATURES];
 static uint64_t remap_deadlist_count = 0;
 
 static int
 dump_one_objset(const char *dsname, void *arg)
 {
 	(void) arg;
 	int error;
 	objset_t *os;
 	spa_feature_t f;
 
 	error = open_objset(dsname, FTAG, &os);
 	if (error != 0)
 		return (0);
 
 	for (f = 0; f < SPA_FEATURES; f++) {
 		if (!dsl_dataset_feature_is_active(dmu_objset_ds(os), f))
 			continue;
 		ASSERT(spa_feature_table[f].fi_flags &
 		    ZFEATURE_FLAG_PER_DATASET);
 		dataset_feature_count[f]++;
 	}
 
 	if (dsl_dataset_remap_deadlist_exists(dmu_objset_ds(os))) {
 		remap_deadlist_count++;
 	}
 
 	for (dsl_bookmark_node_t *dbn =
 	    avl_first(&dmu_objset_ds(os)->ds_bookmarks); dbn != NULL;
 	    dbn = AVL_NEXT(&dmu_objset_ds(os)->ds_bookmarks, dbn)) {
 		mos_obj_refd(dbn->dbn_phys.zbm_redaction_obj);
 		if (dbn->dbn_phys.zbm_redaction_obj != 0)
 			global_feature_count[SPA_FEATURE_REDACTION_BOOKMARKS]++;
 		if (dbn->dbn_phys.zbm_flags & ZBM_FLAG_HAS_FBN)
 			global_feature_count[SPA_FEATURE_BOOKMARK_WRITTEN]++;
 	}
 
 	if (dsl_deadlist_is_open(&dmu_objset_ds(os)->ds_dir->dd_livelist) &&
 	    !dmu_objset_is_snapshot(os)) {
 		global_feature_count[SPA_FEATURE_LIVELIST]++;
 	}
 
 	dump_objset(os);
 	close_objset(os, FTAG);
 	fuid_table_destroy();
 	return (0);
 }
 
 /*
  * Block statistics.
  */
 #define	PSIZE_HISTO_SIZE (SPA_OLD_MAXBLOCKSIZE / SPA_MINBLOCKSIZE + 2)
 typedef struct zdb_blkstats {
 	uint64_t zb_asize;
 	uint64_t zb_lsize;
 	uint64_t zb_psize;
 	uint64_t zb_count;
 	uint64_t zb_gangs;
 	uint64_t zb_ditto_samevdev;
 	uint64_t zb_ditto_same_ms;
 	uint64_t zb_psize_histogram[PSIZE_HISTO_SIZE];
 } zdb_blkstats_t;
 
 /*
  * Extended object types to report deferred frees and dedup auto-ditto blocks.
  */
 #define	ZDB_OT_DEFERRED	(DMU_OT_NUMTYPES + 0)
 #define	ZDB_OT_DITTO	(DMU_OT_NUMTYPES + 1)
 #define	ZDB_OT_OTHER	(DMU_OT_NUMTYPES + 2)
 #define	ZDB_OT_TOTAL	(DMU_OT_NUMTYPES + 3)
 
 static const char *zdb_ot_extname[] = {
 	"deferred free",
 	"dedup ditto",
 	"other",
 	"Total",
 };
 
 #define	ZB_TOTAL	DN_MAX_LEVELS
 #define	SPA_MAX_FOR_16M	(SPA_MAXBLOCKSHIFT+1)
 
 typedef struct zdb_brt_entry {
 	dva_t		zbre_dva;
 	uint64_t	zbre_refcount;
 	avl_node_t	zbre_node;
 } zdb_brt_entry_t;
 
 typedef struct zdb_cb {
 	zdb_blkstats_t	zcb_type[ZB_TOTAL + 1][ZDB_OT_TOTAL + 1];
 	uint64_t	zcb_removing_size;
 	uint64_t	zcb_checkpoint_size;
 	uint64_t	zcb_dedup_asize;
 	uint64_t	zcb_dedup_blocks;
 	uint64_t	zcb_clone_asize;
 	uint64_t	zcb_clone_blocks;
 	uint64_t	zcb_psize_count[SPA_MAX_FOR_16M];
 	uint64_t	zcb_lsize_count[SPA_MAX_FOR_16M];
 	uint64_t	zcb_asize_count[SPA_MAX_FOR_16M];
 	uint64_t	zcb_psize_len[SPA_MAX_FOR_16M];
 	uint64_t	zcb_lsize_len[SPA_MAX_FOR_16M];
 	uint64_t	zcb_asize_len[SPA_MAX_FOR_16M];
 	uint64_t	zcb_psize_total;
 	uint64_t	zcb_lsize_total;
 	uint64_t	zcb_asize_total;
 	uint64_t	zcb_embedded_blocks[NUM_BP_EMBEDDED_TYPES];
 	uint64_t	zcb_embedded_histogram[NUM_BP_EMBEDDED_TYPES]
 	    [BPE_PAYLOAD_SIZE + 1];
 	uint64_t	zcb_start;
 	hrtime_t	zcb_lastprint;
 	uint64_t	zcb_totalasize;
 	uint64_t	zcb_errors[256];
 	int		zcb_readfails;
 	int		zcb_haderrors;
 	spa_t		*zcb_spa;
 	uint32_t	**zcb_vd_obsolete_counts;
 	avl_tree_t	zcb_brt;
 	boolean_t	zcb_brt_is_active;
 } zdb_cb_t;
 
 /* test if two DVA offsets from same vdev are within the same metaslab */
 static boolean_t
 same_metaslab(spa_t *spa, uint64_t vdev, uint64_t off1, uint64_t off2)
 {
 	vdev_t *vd = vdev_lookup_top(spa, vdev);
 	uint64_t ms_shift = vd->vdev_ms_shift;
 
 	return ((off1 >> ms_shift) == (off2 >> ms_shift));
 }
 
 /*
  * Used to simplify reporting of the histogram data.
  */
 typedef struct one_histo {
 	const char *name;
 	uint64_t *count;
 	uint64_t *len;
 	uint64_t cumulative;
 } one_histo_t;
 
 /*
  * The number of separate histograms processed for psize, lsize and asize.
  */
 #define	NUM_HISTO 3
 
 /*
  * This routine will create a fixed column size output of three different
  * histograms showing by blocksize of 512 - 2^ SPA_MAX_FOR_16M
  * the count, length and cumulative length of the psize, lsize and
  * asize blocks.
  *
  * All three types of blocks are listed on a single line
  *
  * By default the table is printed in nicenumber format (e.g. 123K) but
  * if the '-P' parameter is specified then the full raw number (parseable)
  * is printed out.
  */
 static void
 dump_size_histograms(zdb_cb_t *zcb)
 {
 	/*
 	 * A temporary buffer that allows us to convert a number into
 	 * a string using zdb_nicenumber to allow either raw or human
 	 * readable numbers to be output.
 	 */
 	char numbuf[32];
 
 	/*
 	 * Define titles which are used in the headers of the tables
 	 * printed by this routine.
 	 */
 	const char blocksize_title1[] = "block";
 	const char blocksize_title2[] = "size";
 	const char count_title[] = "Count";
 	const char length_title[] = "Size";
 	const char cumulative_title[] = "Cum.";
 
 	/*
 	 * Setup the histogram arrays (psize, lsize, and asize).
 	 */
 	one_histo_t parm_histo[NUM_HISTO];
 
 	parm_histo[0].name = "psize";
 	parm_histo[0].count = zcb->zcb_psize_count;
 	parm_histo[0].len = zcb->zcb_psize_len;
 	parm_histo[0].cumulative = 0;
 
 	parm_histo[1].name = "lsize";
 	parm_histo[1].count = zcb->zcb_lsize_count;
 	parm_histo[1].len = zcb->zcb_lsize_len;
 	parm_histo[1].cumulative = 0;
 
 	parm_histo[2].name = "asize";
 	parm_histo[2].count = zcb->zcb_asize_count;
 	parm_histo[2].len = zcb->zcb_asize_len;
 	parm_histo[2].cumulative = 0;
 
 
 	(void) printf("\nBlock Size Histogram\n");
 	/*
 	 * Print the first line titles
 	 */
 	if (dump_opt['P'])
 		(void) printf("\n%s\t", blocksize_title1);
 	else
 		(void) printf("\n%7s   ", blocksize_title1);
 
 	for (int j = 0; j < NUM_HISTO; j++) {
 		if (dump_opt['P']) {
 			if (j < NUM_HISTO - 1) {
 				(void) printf("%s\t\t\t", parm_histo[j].name);
 			} else {
 				/* Don't print trailing spaces */
 				(void) printf("  %s", parm_histo[j].name);
 			}
 		} else {
 			if (j < NUM_HISTO - 1) {
 				/* Left aligned strings in the output */
 				(void) printf("%-7s              ",
 				    parm_histo[j].name);
 			} else {
 				/* Don't print trailing spaces */
 				(void) printf("%s", parm_histo[j].name);
 			}
 		}
 	}
 	(void) printf("\n");
 
 	/*
 	 * Print the second line titles
 	 */
 	if (dump_opt['P']) {
 		(void) printf("%s\t", blocksize_title2);
 	} else {
 		(void) printf("%7s ", blocksize_title2);
 	}
 
 	for (int i = 0; i < NUM_HISTO; i++) {
 		if (dump_opt['P']) {
 			(void) printf("%s\t%s\t%s\t",
 			    count_title, length_title, cumulative_title);
 		} else {
 			(void) printf("%7s%7s%7s",
 			    count_title, length_title, cumulative_title);
 		}
 	}
 	(void) printf("\n");
 
 	/*
 	 * Print the rows
 	 */
 	for (int i = SPA_MINBLOCKSHIFT; i < SPA_MAX_FOR_16M; i++) {
 
 		/*
 		 * Print the first column showing the blocksize
 		 */
 		zdb_nicenum((1ULL << i), numbuf, sizeof (numbuf));
 
 		if (dump_opt['P']) {
 			printf("%s", numbuf);
 		} else {
 			printf("%7s:", numbuf);
 		}
 
 		/*
 		 * Print the remaining set of 3 columns per size:
 		 * for psize, lsize and asize
 		 */
 		for (int j = 0; j < NUM_HISTO; j++) {
 			parm_histo[j].cumulative += parm_histo[j].len[i];
 
 			zdb_nicenum(parm_histo[j].count[i],
 			    numbuf, sizeof (numbuf));
 			if (dump_opt['P'])
 				(void) printf("\t%s", numbuf);
 			else
 				(void) printf("%7s", numbuf);
 
 			zdb_nicenum(parm_histo[j].len[i],
 			    numbuf, sizeof (numbuf));
 			if (dump_opt['P'])
 				(void) printf("\t%s", numbuf);
 			else
 				(void) printf("%7s", numbuf);
 
 			zdb_nicenum(parm_histo[j].cumulative,
 			    numbuf, sizeof (numbuf));
 			if (dump_opt['P'])
 				(void) printf("\t%s", numbuf);
 			else
 				(void) printf("%7s", numbuf);
 		}
 		(void) printf("\n");
 	}
 }
 
 static void
 zdb_count_block(zdb_cb_t *zcb, zilog_t *zilog, const blkptr_t *bp,
     dmu_object_type_t type)
 {
 	uint64_t refcnt = 0;
 	int i;
 
 	ASSERT(type < ZDB_OT_TOTAL);
 
 	if (zilog && zil_bp_tree_add(zilog, bp) != 0)
 		return;
 
 	spa_config_enter(zcb->zcb_spa, SCL_CONFIG, FTAG, RW_READER);
 
 	for (i = 0; i < 4; i++) {
 		int l = (i < 2) ? BP_GET_LEVEL(bp) : ZB_TOTAL;
 		int t = (i & 1) ? type : ZDB_OT_TOTAL;
 		int equal;
 		zdb_blkstats_t *zb = &zcb->zcb_type[l][t];
 
 		zb->zb_asize += BP_GET_ASIZE(bp);
 		zb->zb_lsize += BP_GET_LSIZE(bp);
 		zb->zb_psize += BP_GET_PSIZE(bp);
 		zb->zb_count++;
 
 		/*
 		 * The histogram is only big enough to record blocks up to
 		 * SPA_OLD_MAXBLOCKSIZE; larger blocks go into the last,
 		 * "other", bucket.
 		 */
 		unsigned idx = BP_GET_PSIZE(bp) >> SPA_MINBLOCKSHIFT;
 		idx = MIN(idx, SPA_OLD_MAXBLOCKSIZE / SPA_MINBLOCKSIZE + 1);
 		zb->zb_psize_histogram[idx]++;
 
 		zb->zb_gangs += BP_COUNT_GANG(bp);
 
 		switch (BP_GET_NDVAS(bp)) {
 		case 2:
 			if (DVA_GET_VDEV(&bp->blk_dva[0]) ==
 			    DVA_GET_VDEV(&bp->blk_dva[1])) {
 				zb->zb_ditto_samevdev++;
 
 				if (same_metaslab(zcb->zcb_spa,
 				    DVA_GET_VDEV(&bp->blk_dva[0]),
 				    DVA_GET_OFFSET(&bp->blk_dva[0]),
 				    DVA_GET_OFFSET(&bp->blk_dva[1])))
 					zb->zb_ditto_same_ms++;
 			}
 			break;
 		case 3:
 			equal = (DVA_GET_VDEV(&bp->blk_dva[0]) ==
 			    DVA_GET_VDEV(&bp->blk_dva[1])) +
 			    (DVA_GET_VDEV(&bp->blk_dva[0]) ==
 			    DVA_GET_VDEV(&bp->blk_dva[2])) +
 			    (DVA_GET_VDEV(&bp->blk_dva[1]) ==
 			    DVA_GET_VDEV(&bp->blk_dva[2]));
 			if (equal != 0) {
 				zb->zb_ditto_samevdev++;
 
 				if (DVA_GET_VDEV(&bp->blk_dva[0]) ==
 				    DVA_GET_VDEV(&bp->blk_dva[1]) &&
 				    same_metaslab(zcb->zcb_spa,
 				    DVA_GET_VDEV(&bp->blk_dva[0]),
 				    DVA_GET_OFFSET(&bp->blk_dva[0]),
 				    DVA_GET_OFFSET(&bp->blk_dva[1])))
 					zb->zb_ditto_same_ms++;
 				else if (DVA_GET_VDEV(&bp->blk_dva[0]) ==
 				    DVA_GET_VDEV(&bp->blk_dva[2]) &&
 				    same_metaslab(zcb->zcb_spa,
 				    DVA_GET_VDEV(&bp->blk_dva[0]),
 				    DVA_GET_OFFSET(&bp->blk_dva[0]),
 				    DVA_GET_OFFSET(&bp->blk_dva[2])))
 					zb->zb_ditto_same_ms++;
 				else if (DVA_GET_VDEV(&bp->blk_dva[1]) ==
 				    DVA_GET_VDEV(&bp->blk_dva[2]) &&
 				    same_metaslab(zcb->zcb_spa,
 				    DVA_GET_VDEV(&bp->blk_dva[1]),
 				    DVA_GET_OFFSET(&bp->blk_dva[1]),
 				    DVA_GET_OFFSET(&bp->blk_dva[2])))
 					zb->zb_ditto_same_ms++;
 			}
 			break;
 		}
 	}
 
 	spa_config_exit(zcb->zcb_spa, SCL_CONFIG, FTAG);
 
 	if (BP_IS_EMBEDDED(bp)) {
 		zcb->zcb_embedded_blocks[BPE_GET_ETYPE(bp)]++;
 		zcb->zcb_embedded_histogram[BPE_GET_ETYPE(bp)]
 		    [BPE_GET_PSIZE(bp)]++;
 		return;
 	}
 	/*
 	 * The binning histogram bins by powers of two up to
 	 * SPA_MAXBLOCKSIZE rather than creating bins for
 	 * every possible blocksize found in the pool.
 	 */
 	int bin = highbit64(BP_GET_PSIZE(bp)) - 1;
 
 	zcb->zcb_psize_count[bin]++;
 	zcb->zcb_psize_len[bin] += BP_GET_PSIZE(bp);
 	zcb->zcb_psize_total += BP_GET_PSIZE(bp);
 
 	bin = highbit64(BP_GET_LSIZE(bp)) - 1;
 
 	zcb->zcb_lsize_count[bin]++;
 	zcb->zcb_lsize_len[bin] += BP_GET_LSIZE(bp);
 	zcb->zcb_lsize_total += BP_GET_LSIZE(bp);
 
 	bin = highbit64(BP_GET_ASIZE(bp)) - 1;
 
 	zcb->zcb_asize_count[bin]++;
 	zcb->zcb_asize_len[bin] += BP_GET_ASIZE(bp);
 	zcb->zcb_asize_total += BP_GET_ASIZE(bp);
 
 	if (zcb->zcb_brt_is_active && brt_maybe_exists(zcb->zcb_spa, bp)) {
 		/*
 		 * Cloned blocks are special. We need to count them, so we can
 		 * later uncount them when reporting leaked space, and we must
 		 * only claim them them once.
 		 *
 		 * To do this, we keep our own in-memory BRT. For each block
 		 * we haven't seen before, we look it up in the real BRT and
 		 * if its there, we note it and its refcount then proceed as
 		 * normal. If we see the block again, we count it as a clone
 		 * and then give it no further consideration.
 		 */
 		zdb_brt_entry_t zbre_search, *zbre;
 		avl_index_t where;
 
 		zbre_search.zbre_dva = bp->blk_dva[0];
 		zbre = avl_find(&zcb->zcb_brt, &zbre_search, &where);
 		if (zbre != NULL) {
 			zcb->zcb_clone_asize += BP_GET_ASIZE(bp);
 			zcb->zcb_clone_blocks++;
 
 			zbre->zbre_refcount--;
 			if (zbre->zbre_refcount == 0) {
 				avl_remove(&zcb->zcb_brt, zbre);
 				umem_free(zbre, sizeof (zdb_brt_entry_t));
 			}
 			return;
 		}
 
 		uint64_t crefcnt = brt_entry_get_refcount(zcb->zcb_spa, bp);
 		if (crefcnt > 0) {
 			zbre = umem_zalloc(sizeof (zdb_brt_entry_t),
 			    UMEM_NOFAIL);
 			zbre->zbre_dva = bp->blk_dva[0];
 			zbre->zbre_refcount = crefcnt;
 			avl_insert(&zcb->zcb_brt, zbre, where);
 		}
 	}
 
 	if (dump_opt['L'])
 		return;
 
 	if (BP_GET_DEDUP(bp)) {
 		ddt_t *ddt;
 		ddt_entry_t *dde;
 
 		ddt = ddt_select(zcb->zcb_spa, bp);
 		ddt_enter(ddt);
 		dde = ddt_lookup(ddt, bp, B_FALSE);
 
 		if (dde == NULL) {
 			refcnt = 0;
 		} else {
 			ddt_phys_t *ddp = ddt_phys_select(dde, bp);
 			ddt_phys_decref(ddp);
 			refcnt = ddp->ddp_refcnt;
 			if (ddt_phys_total_refcnt(dde) == 0)
 				ddt_remove(ddt, dde);
 		}
 		ddt_exit(ddt);
 	}
 
 	VERIFY3U(zio_wait(zio_claim(NULL, zcb->zcb_spa,
 	    refcnt ? 0 : spa_min_claim_txg(zcb->zcb_spa),
 	    bp, NULL, NULL, ZIO_FLAG_CANFAIL)), ==, 0);
 }
 
 static void
 zdb_blkptr_done(zio_t *zio)
 {
 	spa_t *spa = zio->io_spa;
 	blkptr_t *bp = zio->io_bp;
 	int ioerr = zio->io_error;
 	zdb_cb_t *zcb = zio->io_private;
 	zbookmark_phys_t *zb = &zio->io_bookmark;
 
 	mutex_enter(&spa->spa_scrub_lock);
 	spa->spa_load_verify_bytes -= BP_GET_PSIZE(bp);
 	cv_broadcast(&spa->spa_scrub_io_cv);
 
 	if (ioerr && !(zio->io_flags & ZIO_FLAG_SPECULATIVE)) {
 		char blkbuf[BP_SPRINTF_LEN];
 
 		zcb->zcb_haderrors = 1;
 		zcb->zcb_errors[ioerr]++;
 
 		if (dump_opt['b'] >= 2)
 			snprintf_blkptr(blkbuf, sizeof (blkbuf), bp);
 		else
 			blkbuf[0] = '\0';
 
 		(void) printf("zdb_blkptr_cb: "
 		    "Got error %d reading "
 		    "<%llu, %llu, %lld, %llx> %s -- skipping\n",
 		    ioerr,
 		    (u_longlong_t)zb->zb_objset,
 		    (u_longlong_t)zb->zb_object,
 		    (u_longlong_t)zb->zb_level,
 		    (u_longlong_t)zb->zb_blkid,
 		    blkbuf);
 	}
 	mutex_exit(&spa->spa_scrub_lock);
 
 	abd_free(zio->io_abd);
 }
 
 static int
 zdb_blkptr_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
     const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg)
 {
 	zdb_cb_t *zcb = arg;
 	dmu_object_type_t type;
 	boolean_t is_metadata;
 
 	if (zb->zb_level == ZB_DNODE_LEVEL)
 		return (0);
 
 	if (dump_opt['b'] >= 5 && bp->blk_birth > 0) {
 		char blkbuf[BP_SPRINTF_LEN];
 		snprintf_blkptr(blkbuf, sizeof (blkbuf), bp);
 		(void) printf("objset %llu object %llu "
 		    "level %lld offset 0x%llx %s\n",
 		    (u_longlong_t)zb->zb_objset,
 		    (u_longlong_t)zb->zb_object,
 		    (longlong_t)zb->zb_level,
 		    (u_longlong_t)blkid2offset(dnp, bp, zb),
 		    blkbuf);
 	}
 
 	if (BP_IS_HOLE(bp) || BP_IS_REDACTED(bp))
 		return (0);
 
 	type = BP_GET_TYPE(bp);
 
 	zdb_count_block(zcb, zilog, bp,
 	    (type & DMU_OT_NEWTYPE) ? ZDB_OT_OTHER : type);
 
 	is_metadata = (BP_GET_LEVEL(bp) != 0 || DMU_OT_IS_METADATA(type));
 
 	if (!BP_IS_EMBEDDED(bp) &&
 	    (dump_opt['c'] > 1 || (dump_opt['c'] && is_metadata))) {
 		size_t size = BP_GET_PSIZE(bp);
 		abd_t *abd = abd_alloc(size, B_FALSE);
 		int flags = ZIO_FLAG_CANFAIL | ZIO_FLAG_SCRUB | ZIO_FLAG_RAW;
 
 		/* If it's an intent log block, failure is expected. */
 		if (zb->zb_level == ZB_ZIL_LEVEL)
 			flags |= ZIO_FLAG_SPECULATIVE;
 
 		mutex_enter(&spa->spa_scrub_lock);
 		while (spa->spa_load_verify_bytes > max_inflight_bytes)
 			cv_wait(&spa->spa_scrub_io_cv, &spa->spa_scrub_lock);
 		spa->spa_load_verify_bytes += size;
 		mutex_exit(&spa->spa_scrub_lock);
 
 		zio_nowait(zio_read(NULL, spa, bp, abd, size,
 		    zdb_blkptr_done, zcb, ZIO_PRIORITY_ASYNC_READ, flags, zb));
 	}
 
 	zcb->zcb_readfails = 0;
 
 	/* only call gethrtime() every 100 blocks */
 	static int iters;
 	if (++iters > 100)
 		iters = 0;
 	else
 		return (0);
 
 	if (dump_opt['b'] < 5 && gethrtime() > zcb->zcb_lastprint + NANOSEC) {
 		uint64_t now = gethrtime();
 		char buf[10];
 		uint64_t bytes = zcb->zcb_type[ZB_TOTAL][ZDB_OT_TOTAL].zb_asize;
 		uint64_t kb_per_sec =
 		    1 + bytes / (1 + ((now - zcb->zcb_start) / 1000 / 1000));
 		uint64_t sec_remaining =
 		    (zcb->zcb_totalasize - bytes) / 1024 / kb_per_sec;
 
 		/* make sure nicenum has enough space */
 		_Static_assert(sizeof (buf) >= NN_NUMBUF_SZ, "buf truncated");
 
 		zfs_nicebytes(bytes, buf, sizeof (buf));
 		(void) fprintf(stderr,
 		    "\r%5s completed (%4"PRIu64"MB/s) "
 		    "estimated time remaining: "
 		    "%"PRIu64"hr %02"PRIu64"min %02"PRIu64"sec        ",
 		    buf, kb_per_sec / 1024,
 		    sec_remaining / 60 / 60,
 		    sec_remaining / 60 % 60,
 		    sec_remaining % 60);
 
 		zcb->zcb_lastprint = now;
 	}
 
 	return (0);
 }
 
 static void
 zdb_leak(void *arg, uint64_t start, uint64_t size)
 {
 	vdev_t *vd = arg;
 
 	(void) printf("leaked space: vdev %llu, offset 0x%llx, size %llu\n",
 	    (u_longlong_t)vd->vdev_id, (u_longlong_t)start, (u_longlong_t)size);
 }
 
 static metaslab_ops_t zdb_metaslab_ops = {
 	NULL	/* alloc */
 };
 
 static int
 load_unflushed_svr_segs_cb(spa_t *spa, space_map_entry_t *sme,
     uint64_t txg, void *arg)
 {
 	spa_vdev_removal_t *svr = arg;
 
 	uint64_t offset = sme->sme_offset;
 	uint64_t size = sme->sme_run;
 
 	/* skip vdevs we don't care about */
 	if (sme->sme_vdev != svr->svr_vdev_id)
 		return (0);
 
 	vdev_t *vd = vdev_lookup_top(spa, sme->sme_vdev);
 	metaslab_t *ms = vd->vdev_ms[offset >> vd->vdev_ms_shift];
 	ASSERT(sme->sme_type == SM_ALLOC || sme->sme_type == SM_FREE);
 
 	if (txg < metaslab_unflushed_txg(ms))
 		return (0);
 
 	if (sme->sme_type == SM_ALLOC)
 		range_tree_add(svr->svr_allocd_segs, offset, size);
 	else
 		range_tree_remove(svr->svr_allocd_segs, offset, size);
 
 	return (0);
 }
 
 static void
 claim_segment_impl_cb(uint64_t inner_offset, vdev_t *vd, uint64_t offset,
     uint64_t size, void *arg)
 {
 	(void) inner_offset, (void) arg;
 
 	/*
 	 * This callback was called through a remap from
 	 * a device being removed. Therefore, the vdev that
 	 * this callback is applied to is a concrete
 	 * vdev.
 	 */
 	ASSERT(vdev_is_concrete(vd));
 
 	VERIFY0(metaslab_claim_impl(vd, offset, size,
 	    spa_min_claim_txg(vd->vdev_spa)));
 }
 
 static void
 claim_segment_cb(void *arg, uint64_t offset, uint64_t size)
 {
 	vdev_t *vd = arg;
 
 	vdev_indirect_ops.vdev_op_remap(vd, offset, size,
 	    claim_segment_impl_cb, NULL);
 }
 
 /*
  * After accounting for all allocated blocks that are directly referenced,
  * we might have missed a reference to a block from a partially complete
  * (and thus unused) indirect mapping object. We perform a secondary pass
  * through the metaslabs we have already mapped and claim the destination
  * blocks.
  */
 static void
 zdb_claim_removing(spa_t *spa, zdb_cb_t *zcb)
 {
 	if (dump_opt['L'])
 		return;
 
 	if (spa->spa_vdev_removal == NULL)
 		return;
 
 	spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
 
 	spa_vdev_removal_t *svr = spa->spa_vdev_removal;
 	vdev_t *vd = vdev_lookup_top(spa, svr->svr_vdev_id);
 	vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping;
 
 	ASSERT0(range_tree_space(svr->svr_allocd_segs));
 
 	range_tree_t *allocs = range_tree_create(NULL, RANGE_SEG64, NULL, 0, 0);
 	for (uint64_t msi = 0; msi < vd->vdev_ms_count; msi++) {
 		metaslab_t *msp = vd->vdev_ms[msi];
 
 		ASSERT0(range_tree_space(allocs));
 		if (msp->ms_sm != NULL)
 			VERIFY0(space_map_load(msp->ms_sm, allocs, SM_ALLOC));
 		range_tree_vacate(allocs, range_tree_add, svr->svr_allocd_segs);
 	}
 	range_tree_destroy(allocs);
 
 	iterate_through_spacemap_logs(spa, load_unflushed_svr_segs_cb, svr);
 
 	/*
 	 * Clear everything past what has been synced,
 	 * because we have not allocated mappings for
 	 * it yet.
 	 */
 	range_tree_clear(svr->svr_allocd_segs,
 	    vdev_indirect_mapping_max_offset(vim),
 	    vd->vdev_asize - vdev_indirect_mapping_max_offset(vim));
 
 	zcb->zcb_removing_size += range_tree_space(svr->svr_allocd_segs);
 	range_tree_vacate(svr->svr_allocd_segs, claim_segment_cb, vd);
 
 	spa_config_exit(spa, SCL_CONFIG, FTAG);
 }
 
 static int
 increment_indirect_mapping_cb(void *arg, const blkptr_t *bp, boolean_t bp_freed,
     dmu_tx_t *tx)
 {
 	(void) tx;
 	zdb_cb_t *zcb = arg;
 	spa_t *spa = zcb->zcb_spa;
 	vdev_t *vd;
 	const dva_t *dva = &bp->blk_dva[0];
 
 	ASSERT(!bp_freed);
 	ASSERT(!dump_opt['L']);
 	ASSERT3U(BP_GET_NDVAS(bp), ==, 1);
 
 	spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER);
 	vd = vdev_lookup_top(zcb->zcb_spa, DVA_GET_VDEV(dva));
 	ASSERT3P(vd, !=, NULL);
 	spa_config_exit(spa, SCL_VDEV, FTAG);
 
 	ASSERT(vd->vdev_indirect_config.vic_mapping_object != 0);
 	ASSERT3P(zcb->zcb_vd_obsolete_counts[vd->vdev_id], !=, NULL);
 
 	vdev_indirect_mapping_increment_obsolete_count(
 	    vd->vdev_indirect_mapping,
 	    DVA_GET_OFFSET(dva), DVA_GET_ASIZE(dva),
 	    zcb->zcb_vd_obsolete_counts[vd->vdev_id]);
 
 	return (0);
 }
 
 static uint32_t *
 zdb_load_obsolete_counts(vdev_t *vd)
 {
 	vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping;
 	spa_t *spa = vd->vdev_spa;
 	spa_condensing_indirect_phys_t *scip =
 	    &spa->spa_condensing_indirect_phys;
 	uint64_t obsolete_sm_object;
 	uint32_t *counts;
 
 	VERIFY0(vdev_obsolete_sm_object(vd, &obsolete_sm_object));
 	EQUIV(obsolete_sm_object != 0, vd->vdev_obsolete_sm != NULL);
 	counts = vdev_indirect_mapping_load_obsolete_counts(vim);
 	if (vd->vdev_obsolete_sm != NULL) {
 		vdev_indirect_mapping_load_obsolete_spacemap(vim, counts,
 		    vd->vdev_obsolete_sm);
 	}
 	if (scip->scip_vdev == vd->vdev_id &&
 	    scip->scip_prev_obsolete_sm_object != 0) {
 		space_map_t *prev_obsolete_sm = NULL;
 		VERIFY0(space_map_open(&prev_obsolete_sm, spa->spa_meta_objset,
 		    scip->scip_prev_obsolete_sm_object, 0, vd->vdev_asize, 0));
 		vdev_indirect_mapping_load_obsolete_spacemap(vim, counts,
 		    prev_obsolete_sm);
 		space_map_close(prev_obsolete_sm);
 	}
 	return (counts);
 }
 
 static void
 zdb_ddt_leak_init(spa_t *spa, zdb_cb_t *zcb)
 {
 	ddt_bookmark_t ddb = {0};
 	ddt_entry_t dde;
 	int error;
 	int p;
 
 	ASSERT(!dump_opt['L']);
 
 	while ((error = ddt_walk(spa, &ddb, &dde)) == 0) {
 		blkptr_t blk;
 		ddt_phys_t *ddp = dde.dde_phys;
 
 		if (ddb.ddb_class == DDT_CLASS_UNIQUE)
 			return;
 
 		ASSERT(ddt_phys_total_refcnt(&dde) > 1);
 
 		for (p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
 			if (ddp->ddp_phys_birth == 0)
 				continue;
 			ddt_bp_create(ddb.ddb_checksum,
 			    &dde.dde_key, ddp, &blk);
 			if (p == DDT_PHYS_DITTO) {
 				zdb_count_block(zcb, NULL, &blk, ZDB_OT_DITTO);
 			} else {
 				zcb->zcb_dedup_asize +=
 				    BP_GET_ASIZE(&blk) * (ddp->ddp_refcnt - 1);
 				zcb->zcb_dedup_blocks++;
 			}
 		}
 		ddt_t *ddt = spa->spa_ddt[ddb.ddb_checksum];
 		ddt_enter(ddt);
 		VERIFY(ddt_lookup(ddt, &blk, B_TRUE) != NULL);
 		ddt_exit(ddt);
 	}
 
 	ASSERT(error == ENOENT);
 }
 
 typedef struct checkpoint_sm_exclude_entry_arg {
 	vdev_t *cseea_vd;
 	uint64_t cseea_checkpoint_size;
 } checkpoint_sm_exclude_entry_arg_t;
 
 static int
 checkpoint_sm_exclude_entry_cb(space_map_entry_t *sme, void *arg)
 {
 	checkpoint_sm_exclude_entry_arg_t *cseea = arg;
 	vdev_t *vd = cseea->cseea_vd;
 	metaslab_t *ms = vd->vdev_ms[sme->sme_offset >> vd->vdev_ms_shift];
 	uint64_t end = sme->sme_offset + sme->sme_run;
 
 	ASSERT(sme->sme_type == SM_FREE);
 
 	/*
 	 * Since the vdev_checkpoint_sm exists in the vdev level
 	 * and the ms_sm space maps exist in the metaslab level,
 	 * an entry in the checkpoint space map could theoretically
 	 * cross the boundaries of the metaslab that it belongs.
 	 *
 	 * In reality, because of the way that we populate and
 	 * manipulate the checkpoint's space maps currently,
 	 * there shouldn't be any entries that cross metaslabs.
 	 * Hence the assertion below.
 	 *
 	 * That said, there is no fundamental requirement that
 	 * the checkpoint's space map entries should not cross
 	 * metaslab boundaries. So if needed we could add code
 	 * that handles metaslab-crossing segments in the future.
 	 */
 	VERIFY3U(sme->sme_offset, >=, ms->ms_start);
 	VERIFY3U(end, <=, ms->ms_start + ms->ms_size);
 
 	/*
 	 * By removing the entry from the allocated segments we
 	 * also verify that the entry is there to begin with.
 	 */
 	mutex_enter(&ms->ms_lock);
 	range_tree_remove(ms->ms_allocatable, sme->sme_offset, sme->sme_run);
 	mutex_exit(&ms->ms_lock);
 
 	cseea->cseea_checkpoint_size += sme->sme_run;
 	return (0);
 }
 
 static void
 zdb_leak_init_vdev_exclude_checkpoint(vdev_t *vd, zdb_cb_t *zcb)
 {
 	spa_t *spa = vd->vdev_spa;
 	space_map_t *checkpoint_sm = NULL;
 	uint64_t checkpoint_sm_obj;
 
 	/*
 	 * If there is no vdev_top_zap, we are in a pool whose
 	 * version predates the pool checkpoint feature.
 	 */
 	if (vd->vdev_top_zap == 0)
 		return;
 
 	/*
 	 * If there is no reference of the vdev_checkpoint_sm in
 	 * the vdev_top_zap, then one of the following scenarios
 	 * is true:
 	 *
 	 * 1] There is no checkpoint
 	 * 2] There is a checkpoint, but no checkpointed blocks
 	 *    have been freed yet
 	 * 3] The current vdev is indirect
 	 *
 	 * In these cases we return immediately.
 	 */
 	if (zap_contains(spa_meta_objset(spa), vd->vdev_top_zap,
 	    VDEV_TOP_ZAP_POOL_CHECKPOINT_SM) != 0)
 		return;
 
 	VERIFY0(zap_lookup(spa_meta_objset(spa), vd->vdev_top_zap,
 	    VDEV_TOP_ZAP_POOL_CHECKPOINT_SM, sizeof (uint64_t), 1,
 	    &checkpoint_sm_obj));
 
 	checkpoint_sm_exclude_entry_arg_t cseea;
 	cseea.cseea_vd = vd;
 	cseea.cseea_checkpoint_size = 0;
 
 	VERIFY0(space_map_open(&checkpoint_sm, spa_meta_objset(spa),
 	    checkpoint_sm_obj, 0, vd->vdev_asize, vd->vdev_ashift));
 
 	VERIFY0(space_map_iterate(checkpoint_sm,
 	    space_map_length(checkpoint_sm),
 	    checkpoint_sm_exclude_entry_cb, &cseea));
 	space_map_close(checkpoint_sm);
 
 	zcb->zcb_checkpoint_size += cseea.cseea_checkpoint_size;
 }
 
 static void
 zdb_leak_init_exclude_checkpoint(spa_t *spa, zdb_cb_t *zcb)
 {
 	ASSERT(!dump_opt['L']);
 
 	vdev_t *rvd = spa->spa_root_vdev;
 	for (uint64_t c = 0; c < rvd->vdev_children; c++) {
 		ASSERT3U(c, ==, rvd->vdev_child[c]->vdev_id);
 		zdb_leak_init_vdev_exclude_checkpoint(rvd->vdev_child[c], zcb);
 	}
 }
 
 static int
 count_unflushed_space_cb(spa_t *spa, space_map_entry_t *sme,
     uint64_t txg, void *arg)
 {
 	int64_t *ualloc_space = arg;
 
 	uint64_t offset = sme->sme_offset;
 	uint64_t vdev_id = sme->sme_vdev;
 
 	vdev_t *vd = vdev_lookup_top(spa, vdev_id);
 	if (!vdev_is_concrete(vd))
 		return (0);
 
 	metaslab_t *ms = vd->vdev_ms[offset >> vd->vdev_ms_shift];
 	ASSERT(sme->sme_type == SM_ALLOC || sme->sme_type == SM_FREE);
 
 	if (txg < metaslab_unflushed_txg(ms))
 		return (0);
 
 	if (sme->sme_type == SM_ALLOC)
 		*ualloc_space += sme->sme_run;
 	else
 		*ualloc_space -= sme->sme_run;
 
 	return (0);
 }
 
 static int64_t
 get_unflushed_alloc_space(spa_t *spa)
 {
 	if (dump_opt['L'])
 		return (0);
 
 	int64_t ualloc_space = 0;
 	iterate_through_spacemap_logs(spa, count_unflushed_space_cb,
 	    &ualloc_space);
 	return (ualloc_space);
 }
 
 static int
 load_unflushed_cb(spa_t *spa, space_map_entry_t *sme, uint64_t txg, void *arg)
 {
 	maptype_t *uic_maptype = arg;
 
 	uint64_t offset = sme->sme_offset;
 	uint64_t size = sme->sme_run;
 	uint64_t vdev_id = sme->sme_vdev;
 
 	vdev_t *vd = vdev_lookup_top(spa, vdev_id);
 
 	/* skip indirect vdevs */
 	if (!vdev_is_concrete(vd))
 		return (0);
 
 	metaslab_t *ms = vd->vdev_ms[offset >> vd->vdev_ms_shift];
 
 	ASSERT(sme->sme_type == SM_ALLOC || sme->sme_type == SM_FREE);
 	ASSERT(*uic_maptype == SM_ALLOC || *uic_maptype == SM_FREE);
 
 	if (txg < metaslab_unflushed_txg(ms))
 		return (0);
 
 	if (*uic_maptype == sme->sme_type)
 		range_tree_add(ms->ms_allocatable, offset, size);
 	else
 		range_tree_remove(ms->ms_allocatable, offset, size);
 
 	return (0);
 }
 
 static void
 load_unflushed_to_ms_allocatables(spa_t *spa, maptype_t maptype)
 {
 	iterate_through_spacemap_logs(spa, load_unflushed_cb, &maptype);
 }
 
 static void
 load_concrete_ms_allocatable_trees(spa_t *spa, maptype_t maptype)
 {
 	vdev_t *rvd = spa->spa_root_vdev;
 	for (uint64_t i = 0; i < rvd->vdev_children; i++) {
 		vdev_t *vd = rvd->vdev_child[i];
 
 		ASSERT3U(i, ==, vd->vdev_id);
 
 		if (vd->vdev_ops == &vdev_indirect_ops)
 			continue;
 
 		for (uint64_t m = 0; m < vd->vdev_ms_count; m++) {
 			metaslab_t *msp = vd->vdev_ms[m];
 
 			(void) fprintf(stderr,
 			    "\rloading concrete vdev %llu, "
 			    "metaslab %llu of %llu ...",
 			    (longlong_t)vd->vdev_id,
 			    (longlong_t)msp->ms_id,
 			    (longlong_t)vd->vdev_ms_count);
 
 			mutex_enter(&msp->ms_lock);
 			range_tree_vacate(msp->ms_allocatable, NULL, NULL);
 
 			/*
 			 * We don't want to spend the CPU manipulating the
 			 * size-ordered tree, so clear the range_tree ops.
 			 */
 			msp->ms_allocatable->rt_ops = NULL;
 
 			if (msp->ms_sm != NULL) {
 				VERIFY0(space_map_load(msp->ms_sm,
 				    msp->ms_allocatable, maptype));
 			}
 			if (!msp->ms_loaded)
 				msp->ms_loaded = B_TRUE;
 			mutex_exit(&msp->ms_lock);
 		}
 	}
 
 	load_unflushed_to_ms_allocatables(spa, maptype);
 }
 
 /*
  * vm_idxp is an in-out parameter which (for indirect vdevs) is the
  * index in vim_entries that has the first entry in this metaslab.
  * On return, it will be set to the first entry after this metaslab.
  */
 static void
 load_indirect_ms_allocatable_tree(vdev_t *vd, metaslab_t *msp,
     uint64_t *vim_idxp)
 {
 	vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping;
 
 	mutex_enter(&msp->ms_lock);
 	range_tree_vacate(msp->ms_allocatable, NULL, NULL);
 
 	/*
 	 * We don't want to spend the CPU manipulating the
 	 * size-ordered tree, so clear the range_tree ops.
 	 */
 	msp->ms_allocatable->rt_ops = NULL;
 
 	for (; *vim_idxp < vdev_indirect_mapping_num_entries(vim);
 	    (*vim_idxp)++) {
 		vdev_indirect_mapping_entry_phys_t *vimep =
 		    &vim->vim_entries[*vim_idxp];
 		uint64_t ent_offset = DVA_MAPPING_GET_SRC_OFFSET(vimep);
 		uint64_t ent_len = DVA_GET_ASIZE(&vimep->vimep_dst);
 		ASSERT3U(ent_offset, >=, msp->ms_start);
 		if (ent_offset >= msp->ms_start + msp->ms_size)
 			break;
 
 		/*
 		 * Mappings do not cross metaslab boundaries,
 		 * because we create them by walking the metaslabs.
 		 */
 		ASSERT3U(ent_offset + ent_len, <=,
 		    msp->ms_start + msp->ms_size);
 		range_tree_add(msp->ms_allocatable, ent_offset, ent_len);
 	}
 
 	if (!msp->ms_loaded)
 		msp->ms_loaded = B_TRUE;
 	mutex_exit(&msp->ms_lock);
 }
 
 static void
 zdb_leak_init_prepare_indirect_vdevs(spa_t *spa, zdb_cb_t *zcb)
 {
 	ASSERT(!dump_opt['L']);
 
 	vdev_t *rvd = spa->spa_root_vdev;
 	for (uint64_t c = 0; c < rvd->vdev_children; c++) {
 		vdev_t *vd = rvd->vdev_child[c];
 
 		ASSERT3U(c, ==, vd->vdev_id);
 
 		if (vd->vdev_ops != &vdev_indirect_ops)
 			continue;
 
 		/*
 		 * Note: we don't check for mapping leaks on
 		 * removing vdevs because their ms_allocatable's
 		 * are used to look for leaks in allocated space.
 		 */
 		zcb->zcb_vd_obsolete_counts[c] = zdb_load_obsolete_counts(vd);
 
 		/*
 		 * Normally, indirect vdevs don't have any
 		 * metaslabs.  We want to set them up for
 		 * zio_claim().
 		 */
 		vdev_metaslab_group_create(vd);
 		VERIFY0(vdev_metaslab_init(vd, 0));
 
 		vdev_indirect_mapping_t *vim __maybe_unused =
 		    vd->vdev_indirect_mapping;
 		uint64_t vim_idx = 0;
 		for (uint64_t m = 0; m < vd->vdev_ms_count; m++) {
 
 			(void) fprintf(stderr,
 			    "\rloading indirect vdev %llu, "
 			    "metaslab %llu of %llu ...",
 			    (longlong_t)vd->vdev_id,
 			    (longlong_t)vd->vdev_ms[m]->ms_id,
 			    (longlong_t)vd->vdev_ms_count);
 
 			load_indirect_ms_allocatable_tree(vd, vd->vdev_ms[m],
 			    &vim_idx);
 		}
 		ASSERT3U(vim_idx, ==, vdev_indirect_mapping_num_entries(vim));
 	}
 }
 
 static void
 zdb_leak_init(spa_t *spa, zdb_cb_t *zcb)
 {
 	zcb->zcb_spa = spa;
 
 	if (dump_opt['L'])
 		return;
 
 	dsl_pool_t *dp = spa->spa_dsl_pool;
 	vdev_t *rvd = spa->spa_root_vdev;
 
 	/*
 	 * We are going to be changing the meaning of the metaslab's
 	 * ms_allocatable.  Ensure that the allocator doesn't try to
 	 * use the tree.
 	 */
 	spa->spa_normal_class->mc_ops = &zdb_metaslab_ops;
 	spa->spa_log_class->mc_ops = &zdb_metaslab_ops;
 	spa->spa_embedded_log_class->mc_ops = &zdb_metaslab_ops;
 
 	zcb->zcb_vd_obsolete_counts =
 	    umem_zalloc(rvd->vdev_children * sizeof (uint32_t *),
 	    UMEM_NOFAIL);
 
 	/*
 	 * For leak detection, we overload the ms_allocatable trees
 	 * to contain allocated segments instead of free segments.
 	 * As a result, we can't use the normal metaslab_load/unload
 	 * interfaces.
 	 */
 	zdb_leak_init_prepare_indirect_vdevs(spa, zcb);
 	load_concrete_ms_allocatable_trees(spa, SM_ALLOC);
 
 	/*
 	 * On load_concrete_ms_allocatable_trees() we loaded all the
 	 * allocated entries from the ms_sm to the ms_allocatable for
 	 * each metaslab. If the pool has a checkpoint or is in the
 	 * middle of discarding a checkpoint, some of these blocks
 	 * may have been freed but their ms_sm may not have been
 	 * updated because they are referenced by the checkpoint. In
 	 * order to avoid false-positives during leak-detection, we
 	 * go through the vdev's checkpoint space map and exclude all
 	 * its entries from their relevant ms_allocatable.
 	 *
 	 * We also aggregate the space held by the checkpoint and add
 	 * it to zcb_checkpoint_size.
 	 *
 	 * Note that at this point we are also verifying that all the
 	 * entries on the checkpoint_sm are marked as allocated in
 	 * the ms_sm of their relevant metaslab.
 	 * [see comment in checkpoint_sm_exclude_entry_cb()]
 	 */
 	zdb_leak_init_exclude_checkpoint(spa, zcb);
 	ASSERT3U(zcb->zcb_checkpoint_size, ==, spa_get_checkpoint_space(spa));
 
 	/* for cleaner progress output */
 	(void) fprintf(stderr, "\n");
 
 	if (bpobj_is_open(&dp->dp_obsolete_bpobj)) {
 		ASSERT(spa_feature_is_enabled(spa,
 		    SPA_FEATURE_DEVICE_REMOVAL));
 		(void) bpobj_iterate_nofree(&dp->dp_obsolete_bpobj,
 		    increment_indirect_mapping_cb, zcb, NULL);
 	}
 
 	spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
 	zdb_ddt_leak_init(spa, zcb);
 	spa_config_exit(spa, SCL_CONFIG, FTAG);
 }
 
 static boolean_t
 zdb_check_for_obsolete_leaks(vdev_t *vd, zdb_cb_t *zcb)
 {
 	boolean_t leaks = B_FALSE;
 	vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping;
 	uint64_t total_leaked = 0;
 	boolean_t are_precise = B_FALSE;
 
 	ASSERT(vim != NULL);
 
 	for (uint64_t i = 0; i < vdev_indirect_mapping_num_entries(vim); i++) {
 		vdev_indirect_mapping_entry_phys_t *vimep =
 		    &vim->vim_entries[i];
 		uint64_t obsolete_bytes = 0;
 		uint64_t offset = DVA_MAPPING_GET_SRC_OFFSET(vimep);
 		metaslab_t *msp = vd->vdev_ms[offset >> vd->vdev_ms_shift];
 
 		/*
 		 * This is not very efficient but it's easy to
 		 * verify correctness.
 		 */
 		for (uint64_t inner_offset = 0;
 		    inner_offset < DVA_GET_ASIZE(&vimep->vimep_dst);
 		    inner_offset += 1ULL << vd->vdev_ashift) {
 			if (range_tree_contains(msp->ms_allocatable,
 			    offset + inner_offset, 1ULL << vd->vdev_ashift)) {
 				obsolete_bytes += 1ULL << vd->vdev_ashift;
 			}
 		}
 
 		int64_t bytes_leaked = obsolete_bytes -
 		    zcb->zcb_vd_obsolete_counts[vd->vdev_id][i];
 		ASSERT3U(DVA_GET_ASIZE(&vimep->vimep_dst), >=,
 		    zcb->zcb_vd_obsolete_counts[vd->vdev_id][i]);
 
 		VERIFY0(vdev_obsolete_counts_are_precise(vd, &are_precise));
 		if (bytes_leaked != 0 && (are_precise || dump_opt['d'] >= 5)) {
 			(void) printf("obsolete indirect mapping count "
 			    "mismatch on %llu:%llx:%llx : %llx bytes leaked\n",
 			    (u_longlong_t)vd->vdev_id,
 			    (u_longlong_t)DVA_MAPPING_GET_SRC_OFFSET(vimep),
 			    (u_longlong_t)DVA_GET_ASIZE(&vimep->vimep_dst),
 			    (u_longlong_t)bytes_leaked);
 		}
 		total_leaked += ABS(bytes_leaked);
 	}
 
 	VERIFY0(vdev_obsolete_counts_are_precise(vd, &are_precise));
 	if (!are_precise && total_leaked > 0) {
 		int pct_leaked = total_leaked * 100 /
 		    vdev_indirect_mapping_bytes_mapped(vim);
 		(void) printf("cannot verify obsolete indirect mapping "
 		    "counts of vdev %llu because precise feature was not "
 		    "enabled when it was removed: %d%% (%llx bytes) of mapping"
 		    "unreferenced\n",
 		    (u_longlong_t)vd->vdev_id, pct_leaked,
 		    (u_longlong_t)total_leaked);
 	} else if (total_leaked > 0) {
 		(void) printf("obsolete indirect mapping count mismatch "
 		    "for vdev %llu -- %llx total bytes mismatched\n",
 		    (u_longlong_t)vd->vdev_id,
 		    (u_longlong_t)total_leaked);
 		leaks |= B_TRUE;
 	}
 
 	vdev_indirect_mapping_free_obsolete_counts(vim,
 	    zcb->zcb_vd_obsolete_counts[vd->vdev_id]);
 	zcb->zcb_vd_obsolete_counts[vd->vdev_id] = NULL;
 
 	return (leaks);
 }
 
 static boolean_t
 zdb_leak_fini(spa_t *spa, zdb_cb_t *zcb)
 {
 	if (dump_opt['L'])
 		return (B_FALSE);
 
 	boolean_t leaks = B_FALSE;
 	vdev_t *rvd = spa->spa_root_vdev;
 	for (unsigned c = 0; c < rvd->vdev_children; c++) {
 		vdev_t *vd = rvd->vdev_child[c];
 
 		if (zcb->zcb_vd_obsolete_counts[c] != NULL) {
 			leaks |= zdb_check_for_obsolete_leaks(vd, zcb);
 		}
 
 		for (uint64_t m = 0; m < vd->vdev_ms_count; m++) {
 			metaslab_t *msp = vd->vdev_ms[m];
 			ASSERT3P(msp->ms_group, ==, (msp->ms_group->mg_class ==
 			    spa_embedded_log_class(spa)) ?
 			    vd->vdev_log_mg : vd->vdev_mg);
 
 			/*
 			 * ms_allocatable has been overloaded
 			 * to contain allocated segments. Now that
 			 * we finished traversing all blocks, any
 			 * block that remains in the ms_allocatable
 			 * represents an allocated block that we
 			 * did not claim during the traversal.
 			 * Claimed blocks would have been removed
 			 * from the ms_allocatable.  For indirect
 			 * vdevs, space remaining in the tree
 			 * represents parts of the mapping that are
 			 * not referenced, which is not a bug.
 			 */
 			if (vd->vdev_ops == &vdev_indirect_ops) {
 				range_tree_vacate(msp->ms_allocatable,
 				    NULL, NULL);
 			} else {
 				range_tree_vacate(msp->ms_allocatable,
 				    zdb_leak, vd);
 			}
 			if (msp->ms_loaded) {
 				msp->ms_loaded = B_FALSE;
 			}
 		}
 	}
 
 	umem_free(zcb->zcb_vd_obsolete_counts,
 	    rvd->vdev_children * sizeof (uint32_t *));
 	zcb->zcb_vd_obsolete_counts = NULL;
 
 	return (leaks);
 }
 
 static int
 count_block_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
 {
 	(void) tx;
 	zdb_cb_t *zcb = arg;
 
 	if (dump_opt['b'] >= 5) {
 		char blkbuf[BP_SPRINTF_LEN];
 		snprintf_blkptr(blkbuf, sizeof (blkbuf), bp);
 		(void) printf("[%s] %s\n",
 		    "deferred free", blkbuf);
 	}
 	zdb_count_block(zcb, NULL, bp, ZDB_OT_DEFERRED);
 	return (0);
 }
 
 /*
  * Iterate over livelists which have been destroyed by the user but
  * are still present in the MOS, waiting to be freed
  */
 static void
 iterate_deleted_livelists(spa_t *spa, ll_iter_t func, void *arg)
 {
 	objset_t *mos = spa->spa_meta_objset;
 	uint64_t zap_obj;
 	int err = zap_lookup(mos, DMU_POOL_DIRECTORY_OBJECT,
 	    DMU_POOL_DELETED_CLONES, sizeof (uint64_t), 1, &zap_obj);
 	if (err == ENOENT)
 		return;
 	ASSERT0(err);
 
 	zap_cursor_t zc;
 	zap_attribute_t attr;
 	dsl_deadlist_t ll;
 	/* NULL out os prior to dsl_deadlist_open in case it's garbage */
 	ll.dl_os = NULL;
 	for (zap_cursor_init(&zc, mos, zap_obj);
 	    zap_cursor_retrieve(&zc, &attr) == 0;
 	    (void) zap_cursor_advance(&zc)) {
 		dsl_deadlist_open(&ll, mos, attr.za_first_integer);
 		func(&ll, arg);
 		dsl_deadlist_close(&ll);
 	}
 	zap_cursor_fini(&zc);
 }
 
 static int
 bpobj_count_block_cb(void *arg, const blkptr_t *bp, boolean_t bp_freed,
     dmu_tx_t *tx)
 {
 	ASSERT(!bp_freed);
 	return (count_block_cb(arg, bp, tx));
 }
 
 static int
 livelist_entry_count_blocks_cb(void *args, dsl_deadlist_entry_t *dle)
 {
 	zdb_cb_t *zbc = args;
 	bplist_t blks;
 	bplist_create(&blks);
 	/* determine which blocks have been alloc'd but not freed */
 	VERIFY0(dsl_process_sub_livelist(&dle->dle_bpobj, &blks, NULL, NULL));
 	/* count those blocks */
 	(void) bplist_iterate(&blks, count_block_cb, zbc, NULL);
 	bplist_destroy(&blks);
 	return (0);
 }
 
 static void
 livelist_count_blocks(dsl_deadlist_t *ll, void *arg)
 {
 	dsl_deadlist_iterate(ll, livelist_entry_count_blocks_cb, arg);
 }
 
 /*
  * Count the blocks in the livelists that have been destroyed by the user
  * but haven't yet been freed.
  */
 static void
 deleted_livelists_count_blocks(spa_t *spa, zdb_cb_t *zbc)
 {
 	iterate_deleted_livelists(spa, livelist_count_blocks, zbc);
 }
 
 static void
 dump_livelist_cb(dsl_deadlist_t *ll, void *arg)
 {
 	ASSERT3P(arg, ==, NULL);
 	global_feature_count[SPA_FEATURE_LIVELIST]++;
 	dump_blkptr_list(ll, "Deleted Livelist");
 	dsl_deadlist_iterate(ll, sublivelist_verify_lightweight, NULL);
 }
 
 /*
  * Print out, register object references to, and increment feature counts for
  * livelists that have been destroyed by the user but haven't yet been freed.
  */
 static void
 deleted_livelists_dump_mos(spa_t *spa)
 {
 	uint64_t zap_obj;
 	objset_t *mos = spa->spa_meta_objset;
 	int err = zap_lookup(mos, DMU_POOL_DIRECTORY_OBJECT,
 	    DMU_POOL_DELETED_CLONES, sizeof (uint64_t), 1, &zap_obj);
 	if (err == ENOENT)
 		return;
 	mos_obj_refd(zap_obj);
 	iterate_deleted_livelists(spa, dump_livelist_cb, NULL);
 }
 
 static int
 zdb_brt_entry_compare(const void *zcn1, const void *zcn2)
 {
 	const dva_t *dva1 = &((const zdb_brt_entry_t *)zcn1)->zbre_dva;
 	const dva_t *dva2 = &((const zdb_brt_entry_t *)zcn2)->zbre_dva;
 	int cmp;
 
 	cmp = TREE_CMP(DVA_GET_VDEV(dva1), DVA_GET_VDEV(dva2));
 	if (cmp == 0)
 		cmp = TREE_CMP(DVA_GET_OFFSET(dva1), DVA_GET_OFFSET(dva2));
 
 	return (cmp);
 }
 
 static int
 dump_block_stats(spa_t *spa)
 {
 	zdb_cb_t *zcb;
 	zdb_blkstats_t *zb, *tzb;
 	uint64_t norm_alloc, norm_space, total_alloc, total_found;
 	int flags = TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA |
 	    TRAVERSE_NO_DECRYPT | TRAVERSE_HARD;
 	boolean_t leaks = B_FALSE;
 	int e, c, err;
 	bp_embedded_type_t i;
 
 	zcb = umem_zalloc(sizeof (zdb_cb_t), UMEM_NOFAIL);
 
 	if (spa_feature_is_active(spa, SPA_FEATURE_BLOCK_CLONING)) {
 		avl_create(&zcb->zcb_brt, zdb_brt_entry_compare,
 		    sizeof (zdb_brt_entry_t),
 		    offsetof(zdb_brt_entry_t, zbre_node));
 		zcb->zcb_brt_is_active = B_TRUE;
 	}
 
 	(void) printf("\nTraversing all blocks %s%s%s%s%s...\n\n",
 	    (dump_opt['c'] || !dump_opt['L']) ? "to verify " : "",
 	    (dump_opt['c'] == 1) ? "metadata " : "",
 	    dump_opt['c'] ? "checksums " : "",
 	    (dump_opt['c'] && !dump_opt['L']) ? "and verify " : "",
 	    !dump_opt['L'] ? "nothing leaked " : "");
 
 	/*
 	 * When leak detection is enabled we load all space maps as SM_ALLOC
 	 * maps, then traverse the pool claiming each block we discover. If
 	 * the pool is perfectly consistent, the segment trees will be empty
 	 * when we're done. Anything left over is a leak; any block we can't
 	 * claim (because it's not part of any space map) is a double
 	 * allocation, reference to a freed block, or an unclaimed log block.
 	 *
 	 * When leak detection is disabled (-L option) we still traverse the
 	 * pool claiming each block we discover, but we skip opening any space
 	 * maps.
 	 */
 	zdb_leak_init(spa, zcb);
 
 	/*
 	 * If there's a deferred-free bplist, process that first.
 	 */
 	(void) bpobj_iterate_nofree(&spa->spa_deferred_bpobj,
 	    bpobj_count_block_cb, zcb, NULL);
 
 	if (spa_version(spa) >= SPA_VERSION_DEADLISTS) {
 		(void) bpobj_iterate_nofree(&spa->spa_dsl_pool->dp_free_bpobj,
 		    bpobj_count_block_cb, zcb, NULL);
 	}
 
 	zdb_claim_removing(spa, zcb);
 
 	if (spa_feature_is_active(spa, SPA_FEATURE_ASYNC_DESTROY)) {
 		VERIFY3U(0, ==, bptree_iterate(spa->spa_meta_objset,
 		    spa->spa_dsl_pool->dp_bptree_obj, B_FALSE, count_block_cb,
 		    zcb, NULL));
 	}
 
 	deleted_livelists_count_blocks(spa, zcb);
 
 	if (dump_opt['c'] > 1)
 		flags |= TRAVERSE_PREFETCH_DATA;
 
 	zcb->zcb_totalasize = metaslab_class_get_alloc(spa_normal_class(spa));
 	zcb->zcb_totalasize += metaslab_class_get_alloc(spa_special_class(spa));
 	zcb->zcb_totalasize += metaslab_class_get_alloc(spa_dedup_class(spa));
 	zcb->zcb_totalasize +=
 	    metaslab_class_get_alloc(spa_embedded_log_class(spa));
 	zcb->zcb_start = zcb->zcb_lastprint = gethrtime();
 	err = traverse_pool(spa, 0, flags, zdb_blkptr_cb, zcb);
 
 	/*
 	 * If we've traversed the data blocks then we need to wait for those
 	 * I/Os to complete. We leverage "The Godfather" zio to wait on
 	 * all async I/Os to complete.
 	 */
 	if (dump_opt['c']) {
 		for (c = 0; c < max_ncpus; c++) {
 			(void) zio_wait(spa->spa_async_zio_root[c]);
 			spa->spa_async_zio_root[c] = zio_root(spa, NULL, NULL,
 			    ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE |
 			    ZIO_FLAG_GODFATHER);
 		}
 	}
 	ASSERT0(spa->spa_load_verify_bytes);
 
 	/*
 	 * Done after zio_wait() since zcb_haderrors is modified in
 	 * zdb_blkptr_done()
 	 */
 	zcb->zcb_haderrors |= err;
 
 	if (zcb->zcb_haderrors) {
 		(void) printf("\nError counts:\n\n");
 		(void) printf("\t%5s  %s\n", "errno", "count");
 		for (e = 0; e < 256; e++) {
 			if (zcb->zcb_errors[e] != 0) {
 				(void) printf("\t%5d  %llu\n",
 				    e, (u_longlong_t)zcb->zcb_errors[e]);
 			}
 		}
 	}
 
 	/*
 	 * Report any leaked segments.
 	 */
 	leaks |= zdb_leak_fini(spa, zcb);
 
 	tzb = &zcb->zcb_type[ZB_TOTAL][ZDB_OT_TOTAL];
 
 	norm_alloc = metaslab_class_get_alloc(spa_normal_class(spa));
 	norm_space = metaslab_class_get_space(spa_normal_class(spa));
 
 	total_alloc = norm_alloc +
 	    metaslab_class_get_alloc(spa_log_class(spa)) +
 	    metaslab_class_get_alloc(spa_embedded_log_class(spa)) +
 	    metaslab_class_get_alloc(spa_special_class(spa)) +
 	    metaslab_class_get_alloc(spa_dedup_class(spa)) +
 	    get_unflushed_alloc_space(spa);
 	total_found =
 	    tzb->zb_asize - zcb->zcb_dedup_asize - zcb->zcb_clone_asize +
 	    zcb->zcb_removing_size + zcb->zcb_checkpoint_size;
 
 	if (total_found == total_alloc && !dump_opt['L']) {
 		(void) printf("\n\tNo leaks (block sum matches space"
 		    " maps exactly)\n");
 	} else if (!dump_opt['L']) {
 		(void) printf("block traversal size %llu != alloc %llu "
 		    "(%s %lld)\n",
 		    (u_longlong_t)total_found,
 		    (u_longlong_t)total_alloc,
 		    (dump_opt['L']) ? "unreachable" : "leaked",
 		    (longlong_t)(total_alloc - total_found));
 		leaks = B_TRUE;
 	}
 
 	if (tzb->zb_count == 0) {
 		umem_free(zcb, sizeof (zdb_cb_t));
 		return (2);
 	}
 
 	(void) printf("\n");
 	(void) printf("\t%-16s %14llu\n", "bp count:",
 	    (u_longlong_t)tzb->zb_count);
 	(void) printf("\t%-16s %14llu\n", "ganged count:",
 	    (longlong_t)tzb->zb_gangs);
 	(void) printf("\t%-16s %14llu      avg: %6llu\n", "bp logical:",
 	    (u_longlong_t)tzb->zb_lsize,
 	    (u_longlong_t)(tzb->zb_lsize / tzb->zb_count));
 	(void) printf("\t%-16s %14llu      avg: %6llu     compression: %6.2f\n",
 	    "bp physical:", (u_longlong_t)tzb->zb_psize,
 	    (u_longlong_t)(tzb->zb_psize / tzb->zb_count),
 	    (double)tzb->zb_lsize / tzb->zb_psize);
 	(void) printf("\t%-16s %14llu      avg: %6llu     compression: %6.2f\n",
 	    "bp allocated:", (u_longlong_t)tzb->zb_asize,
 	    (u_longlong_t)(tzb->zb_asize / tzb->zb_count),
 	    (double)tzb->zb_lsize / tzb->zb_asize);
 	(void) printf("\t%-16s %14llu    ref>1: %6llu   deduplication: %6.2f\n",
 	    "bp deduped:", (u_longlong_t)zcb->zcb_dedup_asize,
 	    (u_longlong_t)zcb->zcb_dedup_blocks,
 	    (double)zcb->zcb_dedup_asize / tzb->zb_asize + 1.0);
 	(void) printf("\t%-16s %14llu    count: %6llu\n",
 	    "bp cloned:", (u_longlong_t)zcb->zcb_clone_asize,
 	    (u_longlong_t)zcb->zcb_clone_blocks);
 	(void) printf("\t%-16s %14llu     used: %5.2f%%\n", "Normal class:",
 	    (u_longlong_t)norm_alloc, 100.0 * norm_alloc / norm_space);
 
 	if (spa_special_class(spa)->mc_allocator[0].mca_rotor != NULL) {
 		uint64_t alloc = metaslab_class_get_alloc(
 		    spa_special_class(spa));
 		uint64_t space = metaslab_class_get_space(
 		    spa_special_class(spa));
 
 		(void) printf("\t%-16s %14llu     used: %5.2f%%\n",
 		    "Special class", (u_longlong_t)alloc,
 		    100.0 * alloc / space);
 	}
 
 	if (spa_dedup_class(spa)->mc_allocator[0].mca_rotor != NULL) {
 		uint64_t alloc = metaslab_class_get_alloc(
 		    spa_dedup_class(spa));
 		uint64_t space = metaslab_class_get_space(
 		    spa_dedup_class(spa));
 
 		(void) printf("\t%-16s %14llu     used: %5.2f%%\n",
 		    "Dedup class", (u_longlong_t)alloc,
 		    100.0 * alloc / space);
 	}
 
 	if (spa_embedded_log_class(spa)->mc_allocator[0].mca_rotor != NULL) {
 		uint64_t alloc = metaslab_class_get_alloc(
 		    spa_embedded_log_class(spa));
 		uint64_t space = metaslab_class_get_space(
 		    spa_embedded_log_class(spa));
 
 		(void) printf("\t%-16s %14llu     used: %5.2f%%\n",
 		    "Embedded log class", (u_longlong_t)alloc,
 		    100.0 * alloc / space);
 	}
 
 	for (i = 0; i < NUM_BP_EMBEDDED_TYPES; i++) {
 		if (zcb->zcb_embedded_blocks[i] == 0)
 			continue;
 		(void) printf("\n");
 		(void) printf("\tadditional, non-pointer bps of type %u: "
 		    "%10llu\n",
 		    i, (u_longlong_t)zcb->zcb_embedded_blocks[i]);
 
 		if (dump_opt['b'] >= 3) {
 			(void) printf("\t number of (compressed) bytes:  "
 			    "number of bps\n");
 			dump_histogram(zcb->zcb_embedded_histogram[i],
 			    sizeof (zcb->zcb_embedded_histogram[i]) /
 			    sizeof (zcb->zcb_embedded_histogram[i][0]), 0);
 		}
 	}
 
 	if (tzb->zb_ditto_samevdev != 0) {
 		(void) printf("\tDittoed blocks on same vdev: %llu\n",
 		    (longlong_t)tzb->zb_ditto_samevdev);
 	}
 	if (tzb->zb_ditto_same_ms != 0) {
 		(void) printf("\tDittoed blocks in same metaslab: %llu\n",
 		    (longlong_t)tzb->zb_ditto_same_ms);
 	}
 
 	for (uint64_t v = 0; v < spa->spa_root_vdev->vdev_children; v++) {
 		vdev_t *vd = spa->spa_root_vdev->vdev_child[v];
 		vdev_indirect_mapping_t *vim = vd->vdev_indirect_mapping;
 
 		if (vim == NULL) {
 			continue;
 		}
 
 		char mem[32];
 		zdb_nicenum(vdev_indirect_mapping_num_entries(vim),
 		    mem, vdev_indirect_mapping_size(vim));
 
 		(void) printf("\tindirect vdev id %llu has %llu segments "
 		    "(%s in memory)\n",
 		    (longlong_t)vd->vdev_id,
 		    (longlong_t)vdev_indirect_mapping_num_entries(vim), mem);
 	}
 
 	if (dump_opt['b'] >= 2) {
 		int l, t, level;
 		char csize[32], lsize[32], psize[32], asize[32];
 		char avg[32], gang[32];
 		(void) printf("\nBlocks\tLSIZE\tPSIZE\tASIZE"
 		    "\t  avg\t comp\t%%Total\tType\n");
 
 		zfs_blkstat_t *mdstats = umem_zalloc(sizeof (zfs_blkstat_t),
 		    UMEM_NOFAIL);
 
 		for (t = 0; t <= ZDB_OT_TOTAL; t++) {
 			const char *typename;
 
 			/* make sure nicenum has enough space */
 			_Static_assert(sizeof (csize) >= NN_NUMBUF_SZ,
 			    "csize truncated");
 			_Static_assert(sizeof (lsize) >= NN_NUMBUF_SZ,
 			    "lsize truncated");
 			_Static_assert(sizeof (psize) >= NN_NUMBUF_SZ,
 			    "psize truncated");
 			_Static_assert(sizeof (asize) >= NN_NUMBUF_SZ,
 			    "asize truncated");
 			_Static_assert(sizeof (avg) >= NN_NUMBUF_SZ,
 			    "avg truncated");
 			_Static_assert(sizeof (gang) >= NN_NUMBUF_SZ,
 			    "gang truncated");
 
 			if (t < DMU_OT_NUMTYPES)
 				typename = dmu_ot[t].ot_name;
 			else
 				typename = zdb_ot_extname[t - DMU_OT_NUMTYPES];
 
 			if (zcb->zcb_type[ZB_TOTAL][t].zb_asize == 0) {
 				(void) printf("%6s\t%5s\t%5s\t%5s"
 				    "\t%5s\t%5s\t%6s\t%s\n",
 				    "-",
 				    "-",
 				    "-",
 				    "-",
 				    "-",
 				    "-",
 				    "-",
 				    typename);
 				continue;
 			}
 
 			for (l = ZB_TOTAL - 1; l >= -1; l--) {
 				level = (l == -1 ? ZB_TOTAL : l);
 				zb = &zcb->zcb_type[level][t];
 
 				if (zb->zb_asize == 0)
 					continue;
 
 				if (level != ZB_TOTAL && t < DMU_OT_NUMTYPES &&
 				    (level > 0 || DMU_OT_IS_METADATA(t))) {
 					mdstats->zb_count += zb->zb_count;
 					mdstats->zb_lsize += zb->zb_lsize;
 					mdstats->zb_psize += zb->zb_psize;
 					mdstats->zb_asize += zb->zb_asize;
 					mdstats->zb_gangs += zb->zb_gangs;
 				}
 
 				if (dump_opt['b'] < 3 && level != ZB_TOTAL)
 					continue;
 
 				if (level == 0 && zb->zb_asize ==
 				    zcb->zcb_type[ZB_TOTAL][t].zb_asize)
 					continue;
 
 				zdb_nicenum(zb->zb_count, csize,
 				    sizeof (csize));
 				zdb_nicenum(zb->zb_lsize, lsize,
 				    sizeof (lsize));
 				zdb_nicenum(zb->zb_psize, psize,
 				    sizeof (psize));
 				zdb_nicenum(zb->zb_asize, asize,
 				    sizeof (asize));
 				zdb_nicenum(zb->zb_asize / zb->zb_count, avg,
 				    sizeof (avg));
 				zdb_nicenum(zb->zb_gangs, gang, sizeof (gang));
 
 				(void) printf("%6s\t%5s\t%5s\t%5s\t%5s"
 				    "\t%5.2f\t%6.2f\t",
 				    csize, lsize, psize, asize, avg,
 				    (double)zb->zb_lsize / zb->zb_psize,
 				    100.0 * zb->zb_asize / tzb->zb_asize);
 
 				if (level == ZB_TOTAL)
 					(void) printf("%s\n", typename);
 				else
 					(void) printf("    L%d %s\n",
 					    level, typename);
 
 				if (dump_opt['b'] >= 3 && zb->zb_gangs > 0) {
 					(void) printf("\t number of ganged "
 					    "blocks: %s\n", gang);
 				}
 
 				if (dump_opt['b'] >= 4) {
 					(void) printf("psize "
 					    "(in 512-byte sectors): "
 					    "number of blocks\n");
 					dump_histogram(zb->zb_psize_histogram,
 					    PSIZE_HISTO_SIZE, 0);
 				}
 			}
 		}
 		zdb_nicenum(mdstats->zb_count, csize,
 		    sizeof (csize));
 		zdb_nicenum(mdstats->zb_lsize, lsize,
 		    sizeof (lsize));
 		zdb_nicenum(mdstats->zb_psize, psize,
 		    sizeof (psize));
 		zdb_nicenum(mdstats->zb_asize, asize,
 		    sizeof (asize));
 		zdb_nicenum(mdstats->zb_asize / mdstats->zb_count, avg,
 		    sizeof (avg));
 		zdb_nicenum(mdstats->zb_gangs, gang, sizeof (gang));
 
 		(void) printf("%6s\t%5s\t%5s\t%5s\t%5s"
 		    "\t%5.2f\t%6.2f\t",
 		    csize, lsize, psize, asize, avg,
 		    (double)mdstats->zb_lsize / mdstats->zb_psize,
 		    100.0 * mdstats->zb_asize / tzb->zb_asize);
 		(void) printf("%s\n", "Metadata Total");
 
 		/* Output a table summarizing block sizes in the pool */
 		if (dump_opt['b'] >= 2) {
 			dump_size_histograms(zcb);
 		}
 
 		umem_free(mdstats, sizeof (zfs_blkstat_t));
 	}
 
 	(void) printf("\n");
 
 	if (leaks) {
 		umem_free(zcb, sizeof (zdb_cb_t));
 		return (2);
 	}
 
 	if (zcb->zcb_haderrors) {
 		umem_free(zcb, sizeof (zdb_cb_t));
 		return (3);
 	}
 
 	umem_free(zcb, sizeof (zdb_cb_t));
 	return (0);
 }
 
 typedef struct zdb_ddt_entry {
 	ddt_key_t	zdde_key;
 	uint64_t	zdde_ref_blocks;
 	uint64_t	zdde_ref_lsize;
 	uint64_t	zdde_ref_psize;
 	uint64_t	zdde_ref_dsize;
 	avl_node_t	zdde_node;
 } zdb_ddt_entry_t;
 
 static int
 zdb_ddt_add_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
     const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg)
 {
 	(void) zilog, (void) dnp;
 	avl_tree_t *t = arg;
 	avl_index_t where;
 	zdb_ddt_entry_t *zdde, zdde_search;
 
 	if (zb->zb_level == ZB_DNODE_LEVEL || BP_IS_HOLE(bp) ||
 	    BP_IS_EMBEDDED(bp))
 		return (0);
 
 	if (dump_opt['S'] > 1 && zb->zb_level == ZB_ROOT_LEVEL) {
 		(void) printf("traversing objset %llu, %llu objects, "
 		    "%lu blocks so far\n",
 		    (u_longlong_t)zb->zb_objset,
 		    (u_longlong_t)BP_GET_FILL(bp),
 		    avl_numnodes(t));
 	}
 
 	if (BP_IS_HOLE(bp) || BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_OFF ||
 	    BP_GET_LEVEL(bp) > 0 || DMU_OT_IS_METADATA(BP_GET_TYPE(bp)))
 		return (0);
 
 	ddt_key_fill(&zdde_search.zdde_key, bp);
 
 	zdde = avl_find(t, &zdde_search, &where);
 
 	if (zdde == NULL) {
 		zdde = umem_zalloc(sizeof (*zdde), UMEM_NOFAIL);
 		zdde->zdde_key = zdde_search.zdde_key;
 		avl_insert(t, zdde, where);
 	}
 
 	zdde->zdde_ref_blocks += 1;
 	zdde->zdde_ref_lsize += BP_GET_LSIZE(bp);
 	zdde->zdde_ref_psize += BP_GET_PSIZE(bp);
 	zdde->zdde_ref_dsize += bp_get_dsize_sync(spa, bp);
 
 	return (0);
 }
 
 static void
 dump_simulated_ddt(spa_t *spa)
 {
 	avl_tree_t t;
 	void *cookie = NULL;
 	zdb_ddt_entry_t *zdde;
 	ddt_histogram_t ddh_total = {{{0}}};
 	ddt_stat_t dds_total = {0};
 
 	avl_create(&t, ddt_entry_compare,
 	    sizeof (zdb_ddt_entry_t), offsetof(zdb_ddt_entry_t, zdde_node));
 
 	spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
 
 	(void) traverse_pool(spa, 0, TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA |
 	    TRAVERSE_NO_DECRYPT, zdb_ddt_add_cb, &t);
 
 	spa_config_exit(spa, SCL_CONFIG, FTAG);
 
 	while ((zdde = avl_destroy_nodes(&t, &cookie)) != NULL) {
 		ddt_stat_t dds;
 		uint64_t refcnt = zdde->zdde_ref_blocks;
 		ASSERT(refcnt != 0);
 
 		dds.dds_blocks = zdde->zdde_ref_blocks / refcnt;
 		dds.dds_lsize = zdde->zdde_ref_lsize / refcnt;
 		dds.dds_psize = zdde->zdde_ref_psize / refcnt;
 		dds.dds_dsize = zdde->zdde_ref_dsize / refcnt;
 
 		dds.dds_ref_blocks = zdde->zdde_ref_blocks;
 		dds.dds_ref_lsize = zdde->zdde_ref_lsize;
 		dds.dds_ref_psize = zdde->zdde_ref_psize;
 		dds.dds_ref_dsize = zdde->zdde_ref_dsize;
 
 		ddt_stat_add(&ddh_total.ddh_stat[highbit64(refcnt) - 1],
 		    &dds, 0);
 
 		umem_free(zdde, sizeof (*zdde));
 	}
 
 	avl_destroy(&t);
 
 	ddt_histogram_stat(&dds_total, &ddh_total);
 
 	(void) printf("Simulated DDT histogram:\n");
 
 	zpool_dump_ddt(&dds_total, &ddh_total);
 
 	dump_dedup_ratio(&dds_total);
 }
 
 static int
 verify_device_removal_feature_counts(spa_t *spa)
 {
 	uint64_t dr_feature_refcount = 0;
 	uint64_t oc_feature_refcount = 0;
 	uint64_t indirect_vdev_count = 0;
 	uint64_t precise_vdev_count = 0;
 	uint64_t obsolete_counts_object_count = 0;
 	uint64_t obsolete_sm_count = 0;
 	uint64_t obsolete_counts_count = 0;
 	uint64_t scip_count = 0;
 	uint64_t obsolete_bpobj_count = 0;
 	int ret = 0;
 
 	spa_condensing_indirect_phys_t *scip =
 	    &spa->spa_condensing_indirect_phys;
 	if (scip->scip_next_mapping_object != 0) {
 		vdev_t *vd = spa->spa_root_vdev->vdev_child[scip->scip_vdev];
 		ASSERT(scip->scip_prev_obsolete_sm_object != 0);
 		ASSERT3P(vd->vdev_ops, ==, &vdev_indirect_ops);
 
 		(void) printf("Condensing indirect vdev %llu: new mapping "
 		    "object %llu, prev obsolete sm %llu\n",
 		    (u_longlong_t)scip->scip_vdev,
 		    (u_longlong_t)scip->scip_next_mapping_object,
 		    (u_longlong_t)scip->scip_prev_obsolete_sm_object);
 		if (scip->scip_prev_obsolete_sm_object != 0) {
 			space_map_t *prev_obsolete_sm = NULL;
 			VERIFY0(space_map_open(&prev_obsolete_sm,
 			    spa->spa_meta_objset,
 			    scip->scip_prev_obsolete_sm_object,
 			    0, vd->vdev_asize, 0));
 			dump_spacemap(spa->spa_meta_objset, prev_obsolete_sm);
 			(void) printf("\n");
 			space_map_close(prev_obsolete_sm);
 		}
 
 		scip_count += 2;
 	}
 
 	for (uint64_t i = 0; i < spa->spa_root_vdev->vdev_children; i++) {
 		vdev_t *vd = spa->spa_root_vdev->vdev_child[i];
 		vdev_indirect_config_t *vic = &vd->vdev_indirect_config;
 
 		if (vic->vic_mapping_object != 0) {
 			ASSERT(vd->vdev_ops == &vdev_indirect_ops ||
 			    vd->vdev_removing);
 			indirect_vdev_count++;
 
 			if (vd->vdev_indirect_mapping->vim_havecounts) {
 				obsolete_counts_count++;
 			}
 		}
 
 		boolean_t are_precise;
 		VERIFY0(vdev_obsolete_counts_are_precise(vd, &are_precise));
 		if (are_precise) {
 			ASSERT(vic->vic_mapping_object != 0);
 			precise_vdev_count++;
 		}
 
 		uint64_t obsolete_sm_object;
 		VERIFY0(vdev_obsolete_sm_object(vd, &obsolete_sm_object));
 		if (obsolete_sm_object != 0) {
 			ASSERT(vic->vic_mapping_object != 0);
 			obsolete_sm_count++;
 		}
 	}
 
 	(void) feature_get_refcount(spa,
 	    &spa_feature_table[SPA_FEATURE_DEVICE_REMOVAL],
 	    &dr_feature_refcount);
 	(void) feature_get_refcount(spa,
 	    &spa_feature_table[SPA_FEATURE_OBSOLETE_COUNTS],
 	    &oc_feature_refcount);
 
 	if (dr_feature_refcount != indirect_vdev_count) {
 		ret = 1;
 		(void) printf("Number of indirect vdevs (%llu) " \
 		    "does not match feature count (%llu)\n",
 		    (u_longlong_t)indirect_vdev_count,
 		    (u_longlong_t)dr_feature_refcount);
 	} else {
 		(void) printf("Verified device_removal feature refcount " \
 		    "of %llu is correct\n",
 		    (u_longlong_t)dr_feature_refcount);
 	}
 
 	if (zap_contains(spa_meta_objset(spa), DMU_POOL_DIRECTORY_OBJECT,
 	    DMU_POOL_OBSOLETE_BPOBJ) == 0) {
 		obsolete_bpobj_count++;
 	}
 
 
 	obsolete_counts_object_count = precise_vdev_count;
 	obsolete_counts_object_count += obsolete_sm_count;
 	obsolete_counts_object_count += obsolete_counts_count;
 	obsolete_counts_object_count += scip_count;
 	obsolete_counts_object_count += obsolete_bpobj_count;
 	obsolete_counts_object_count += remap_deadlist_count;
 
 	if (oc_feature_refcount != obsolete_counts_object_count) {
 		ret = 1;
 		(void) printf("Number of obsolete counts objects (%llu) " \
 		    "does not match feature count (%llu)\n",
 		    (u_longlong_t)obsolete_counts_object_count,
 		    (u_longlong_t)oc_feature_refcount);
 		(void) printf("pv:%llu os:%llu oc:%llu sc:%llu "
 		    "ob:%llu rd:%llu\n",
 		    (u_longlong_t)precise_vdev_count,
 		    (u_longlong_t)obsolete_sm_count,
 		    (u_longlong_t)obsolete_counts_count,
 		    (u_longlong_t)scip_count,
 		    (u_longlong_t)obsolete_bpobj_count,
 		    (u_longlong_t)remap_deadlist_count);
 	} else {
 		(void) printf("Verified indirect_refcount feature refcount " \
 		    "of %llu is correct\n",
 		    (u_longlong_t)oc_feature_refcount);
 	}
 	return (ret);
 }
 
 static void
 zdb_set_skip_mmp(char *target)
 {
 	spa_t *spa;
 
 	/*
 	 * Disable the activity check to allow examination of
 	 * active pools.
 	 */
 	mutex_enter(&spa_namespace_lock);
 	if ((spa = spa_lookup(target)) != NULL) {
 		spa->spa_import_flags |= ZFS_IMPORT_SKIP_MMP;
 	}
 	mutex_exit(&spa_namespace_lock);
 }
 
 #define	BOGUS_SUFFIX "_CHECKPOINTED_UNIVERSE"
 /*
  * Import the checkpointed state of the pool specified by the target
  * parameter as readonly. The function also accepts a pool config
  * as an optional parameter, else it attempts to infer the config by
  * the name of the target pool.
  *
  * Note that the checkpointed state's pool name will be the name of
  * the original pool with the above suffix appended to it. In addition,
  * if the target is not a pool name (e.g. a path to a dataset) then
  * the new_path parameter is populated with the updated path to
  * reflect the fact that we are looking into the checkpointed state.
  *
  * The function returns a newly-allocated copy of the name of the
  * pool containing the checkpointed state. When this copy is no
  * longer needed it should be freed with free(3C). Same thing
  * applies to the new_path parameter if allocated.
  */
 static char *
 import_checkpointed_state(char *target, nvlist_t *cfg, char **new_path)
 {
 	int error = 0;
 	char *poolname, *bogus_name = NULL;
 	boolean_t freecfg = B_FALSE;
 
 	/* If the target is not a pool, the extract the pool name */
 	char *path_start = strchr(target, '/');
 	if (path_start != NULL) {
 		size_t poolname_len = path_start - target;
 		poolname = strndup(target, poolname_len);
 	} else {
 		poolname = target;
 	}
 
 	if (cfg == NULL) {
 		zdb_set_skip_mmp(poolname);
 		error = spa_get_stats(poolname, &cfg, NULL, 0);
 		if (error != 0) {
 			fatal("Tried to read config of pool \"%s\" but "
 			    "spa_get_stats() failed with error %d\n",
 			    poolname, error);
 		}
 		freecfg = B_TRUE;
 	}
 
 	if (asprintf(&bogus_name, "%s%s", poolname, BOGUS_SUFFIX) == -1) {
 		if (target != poolname)
 			free(poolname);
 		return (NULL);
 	}
 	fnvlist_add_string(cfg, ZPOOL_CONFIG_POOL_NAME, bogus_name);
 
 	error = spa_import(bogus_name, cfg, NULL,
 	    ZFS_IMPORT_MISSING_LOG | ZFS_IMPORT_CHECKPOINT |
 	    ZFS_IMPORT_SKIP_MMP);
 	if (freecfg)
 		nvlist_free(cfg);
 	if (error != 0) {
 		fatal("Tried to import pool \"%s\" but spa_import() failed "
 		    "with error %d\n", bogus_name, error);
 	}
 
 	if (new_path != NULL && path_start != NULL) {
 		if (asprintf(new_path, "%s%s", bogus_name, path_start) == -1) {
 			free(bogus_name);
 			if (path_start != NULL)
 				free(poolname);
 			return (NULL);
 		}
 	}
 
 	if (target != poolname)
 		free(poolname);
 
 	return (bogus_name);
 }
 
 typedef struct verify_checkpoint_sm_entry_cb_arg {
 	vdev_t *vcsec_vd;
 
 	/* the following fields are only used for printing progress */
 	uint64_t vcsec_entryid;
 	uint64_t vcsec_num_entries;
 } verify_checkpoint_sm_entry_cb_arg_t;
 
 #define	ENTRIES_PER_PROGRESS_UPDATE 10000
 
 static int
 verify_checkpoint_sm_entry_cb(space_map_entry_t *sme, void *arg)
 {
 	verify_checkpoint_sm_entry_cb_arg_t *vcsec = arg;
 	vdev_t *vd = vcsec->vcsec_vd;
 	metaslab_t *ms = vd->vdev_ms[sme->sme_offset >> vd->vdev_ms_shift];
 	uint64_t end = sme->sme_offset + sme->sme_run;
 
 	ASSERT(sme->sme_type == SM_FREE);
 
 	if ((vcsec->vcsec_entryid % ENTRIES_PER_PROGRESS_UPDATE) == 0) {
 		(void) fprintf(stderr,
 		    "\rverifying vdev %llu, space map entry %llu of %llu ...",
 		    (longlong_t)vd->vdev_id,
 		    (longlong_t)vcsec->vcsec_entryid,
 		    (longlong_t)vcsec->vcsec_num_entries);
 	}
 	vcsec->vcsec_entryid++;
 
 	/*
 	 * See comment in checkpoint_sm_exclude_entry_cb()
 	 */
 	VERIFY3U(sme->sme_offset, >=, ms->ms_start);
 	VERIFY3U(end, <=, ms->ms_start + ms->ms_size);
 
 	/*
 	 * The entries in the vdev_checkpoint_sm should be marked as
 	 * allocated in the checkpointed state of the pool, therefore
 	 * their respective ms_allocateable trees should not contain them.
 	 */
 	mutex_enter(&ms->ms_lock);
 	range_tree_verify_not_present(ms->ms_allocatable,
 	    sme->sme_offset, sme->sme_run);
 	mutex_exit(&ms->ms_lock);
 
 	return (0);
 }
 
 /*
  * Verify that all segments in the vdev_checkpoint_sm are allocated
  * according to the checkpoint's ms_sm (i.e. are not in the checkpoint's
  * ms_allocatable).
  *
  * Do so by comparing the checkpoint space maps (vdev_checkpoint_sm) of
  * each vdev in the current state of the pool to the metaslab space maps
  * (ms_sm) of the checkpointed state of the pool.
  *
  * Note that the function changes the state of the ms_allocatable
  * trees of the current spa_t. The entries of these ms_allocatable
  * trees are cleared out and then repopulated from with the free
  * entries of their respective ms_sm space maps.
  */
 static void
 verify_checkpoint_vdev_spacemaps(spa_t *checkpoint, spa_t *current)
 {
 	vdev_t *ckpoint_rvd = checkpoint->spa_root_vdev;
 	vdev_t *current_rvd = current->spa_root_vdev;
 
 	load_concrete_ms_allocatable_trees(checkpoint, SM_FREE);
 
 	for (uint64_t c = 0; c < ckpoint_rvd->vdev_children; c++) {
 		vdev_t *ckpoint_vd = ckpoint_rvd->vdev_child[c];
 		vdev_t *current_vd = current_rvd->vdev_child[c];
 
 		space_map_t *checkpoint_sm = NULL;
 		uint64_t checkpoint_sm_obj;
 
 		if (ckpoint_vd->vdev_ops == &vdev_indirect_ops) {
 			/*
 			 * Since we don't allow device removal in a pool
 			 * that has a checkpoint, we expect that all removed
 			 * vdevs were removed from the pool before the
 			 * checkpoint.
 			 */
 			ASSERT3P(current_vd->vdev_ops, ==, &vdev_indirect_ops);
 			continue;
 		}
 
 		/*
 		 * If the checkpoint space map doesn't exist, then nothing
 		 * here is checkpointed so there's nothing to verify.
 		 */
 		if (current_vd->vdev_top_zap == 0 ||
 		    zap_contains(spa_meta_objset(current),
 		    current_vd->vdev_top_zap,
 		    VDEV_TOP_ZAP_POOL_CHECKPOINT_SM) != 0)
 			continue;
 
 		VERIFY0(zap_lookup(spa_meta_objset(current),
 		    current_vd->vdev_top_zap, VDEV_TOP_ZAP_POOL_CHECKPOINT_SM,
 		    sizeof (uint64_t), 1, &checkpoint_sm_obj));
 
 		VERIFY0(space_map_open(&checkpoint_sm, spa_meta_objset(current),
 		    checkpoint_sm_obj, 0, current_vd->vdev_asize,
 		    current_vd->vdev_ashift));
 
 		verify_checkpoint_sm_entry_cb_arg_t vcsec;
 		vcsec.vcsec_vd = ckpoint_vd;
 		vcsec.vcsec_entryid = 0;
 		vcsec.vcsec_num_entries =
 		    space_map_length(checkpoint_sm) / sizeof (uint64_t);
 		VERIFY0(space_map_iterate(checkpoint_sm,
 		    space_map_length(checkpoint_sm),
 		    verify_checkpoint_sm_entry_cb, &vcsec));
 		if (dump_opt['m'] > 3)
 			dump_spacemap(current->spa_meta_objset, checkpoint_sm);
 		space_map_close(checkpoint_sm);
 	}
 
 	/*
 	 * If we've added vdevs since we took the checkpoint, ensure
 	 * that their checkpoint space maps are empty.
 	 */
 	if (ckpoint_rvd->vdev_children < current_rvd->vdev_children) {
 		for (uint64_t c = ckpoint_rvd->vdev_children;
 		    c < current_rvd->vdev_children; c++) {
 			vdev_t *current_vd = current_rvd->vdev_child[c];
 			VERIFY3P(current_vd->vdev_checkpoint_sm, ==, NULL);
 		}
 	}
 
 	/* for cleaner progress output */
 	(void) fprintf(stderr, "\n");
 }
 
 /*
  * Verifies that all space that's allocated in the checkpoint is
  * still allocated in the current version, by checking that everything
  * in checkpoint's ms_allocatable (which is actually allocated, not
  * allocatable/free) is not present in current's ms_allocatable.
  *
  * Note that the function changes the state of the ms_allocatable
  * trees of both spas when called. The entries of all ms_allocatable
  * trees are cleared out and then repopulated from their respective
  * ms_sm space maps. In the checkpointed state we load the allocated
  * entries, and in the current state we load the free entries.
  */
 static void
 verify_checkpoint_ms_spacemaps(spa_t *checkpoint, spa_t *current)
 {
 	vdev_t *ckpoint_rvd = checkpoint->spa_root_vdev;
 	vdev_t *current_rvd = current->spa_root_vdev;
 
 	load_concrete_ms_allocatable_trees(checkpoint, SM_ALLOC);
 	load_concrete_ms_allocatable_trees(current, SM_FREE);
 
 	for (uint64_t i = 0; i < ckpoint_rvd->vdev_children; i++) {
 		vdev_t *ckpoint_vd = ckpoint_rvd->vdev_child[i];
 		vdev_t *current_vd = current_rvd->vdev_child[i];
 
 		if (ckpoint_vd->vdev_ops == &vdev_indirect_ops) {
 			/*
 			 * See comment in verify_checkpoint_vdev_spacemaps()
 			 */
 			ASSERT3P(current_vd->vdev_ops, ==, &vdev_indirect_ops);
 			continue;
 		}
 
 		for (uint64_t m = 0; m < ckpoint_vd->vdev_ms_count; m++) {
 			metaslab_t *ckpoint_msp = ckpoint_vd->vdev_ms[m];
 			metaslab_t *current_msp = current_vd->vdev_ms[m];
 
 			(void) fprintf(stderr,
 			    "\rverifying vdev %llu of %llu, "
 			    "metaslab %llu of %llu ...",
 			    (longlong_t)current_vd->vdev_id,
 			    (longlong_t)current_rvd->vdev_children,
 			    (longlong_t)current_vd->vdev_ms[m]->ms_id,
 			    (longlong_t)current_vd->vdev_ms_count);
 
 			/*
 			 * We walk through the ms_allocatable trees that
 			 * are loaded with the allocated blocks from the
 			 * ms_sm spacemaps of the checkpoint. For each
 			 * one of these ranges we ensure that none of them
 			 * exists in the ms_allocatable trees of the
 			 * current state which are loaded with the ranges
 			 * that are currently free.
 			 *
 			 * This way we ensure that none of the blocks that
 			 * are part of the checkpoint were freed by mistake.
 			 */
 			range_tree_walk(ckpoint_msp->ms_allocatable,
 			    (range_tree_func_t *)range_tree_verify_not_present,
 			    current_msp->ms_allocatable);
 		}
 	}
 
 	/* for cleaner progress output */
 	(void) fprintf(stderr, "\n");
 }
 
 static void
 verify_checkpoint_blocks(spa_t *spa)
 {
 	ASSERT(!dump_opt['L']);
 
 	spa_t *checkpoint_spa;
 	char *checkpoint_pool;
 	int error = 0;
 
 	/*
 	 * We import the checkpointed state of the pool (under a different
 	 * name) so we can do verification on it against the current state
 	 * of the pool.
 	 */
 	checkpoint_pool = import_checkpointed_state(spa->spa_name, NULL,
 	    NULL);
 	ASSERT(strcmp(spa->spa_name, checkpoint_pool) != 0);
 
 	error = spa_open(checkpoint_pool, &checkpoint_spa, FTAG);
 	if (error != 0) {
 		fatal("Tried to open pool \"%s\" but spa_open() failed with "
 		    "error %d\n", checkpoint_pool, error);
 	}
 
 	/*
 	 * Ensure that ranges in the checkpoint space maps of each vdev
 	 * are allocated according to the checkpointed state's metaslab
 	 * space maps.
 	 */
 	verify_checkpoint_vdev_spacemaps(checkpoint_spa, spa);
 
 	/*
 	 * Ensure that allocated ranges in the checkpoint's metaslab
 	 * space maps remain allocated in the metaslab space maps of
 	 * the current state.
 	 */
 	verify_checkpoint_ms_spacemaps(checkpoint_spa, spa);
 
 	/*
 	 * Once we are done, we get rid of the checkpointed state.
 	 */
 	spa_close(checkpoint_spa, FTAG);
 	free(checkpoint_pool);
 }
 
 static void
 dump_leftover_checkpoint_blocks(spa_t *spa)
 {
 	vdev_t *rvd = spa->spa_root_vdev;
 
 	for (uint64_t i = 0; i < rvd->vdev_children; i++) {
 		vdev_t *vd = rvd->vdev_child[i];
 
 		space_map_t *checkpoint_sm = NULL;
 		uint64_t checkpoint_sm_obj;
 
 		if (vd->vdev_top_zap == 0)
 			continue;
 
 		if (zap_contains(spa_meta_objset(spa), vd->vdev_top_zap,
 		    VDEV_TOP_ZAP_POOL_CHECKPOINT_SM) != 0)
 			continue;
 
 		VERIFY0(zap_lookup(spa_meta_objset(spa), vd->vdev_top_zap,
 		    VDEV_TOP_ZAP_POOL_CHECKPOINT_SM,
 		    sizeof (uint64_t), 1, &checkpoint_sm_obj));
 
 		VERIFY0(space_map_open(&checkpoint_sm, spa_meta_objset(spa),
 		    checkpoint_sm_obj, 0, vd->vdev_asize, vd->vdev_ashift));
 		dump_spacemap(spa->spa_meta_objset, checkpoint_sm);
 		space_map_close(checkpoint_sm);
 	}
 }
 
 static int
 verify_checkpoint(spa_t *spa)
 {
 	uberblock_t checkpoint;
 	int error;
 
 	if (!spa_feature_is_active(spa, SPA_FEATURE_POOL_CHECKPOINT))
 		return (0);
 
 	error = zap_lookup(spa->spa_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
 	    DMU_POOL_ZPOOL_CHECKPOINT, sizeof (uint64_t),
 	    sizeof (uberblock_t) / sizeof (uint64_t), &checkpoint);
 
 	if (error == ENOENT && !dump_opt['L']) {
 		/*
 		 * If the feature is active but the uberblock is missing
 		 * then we must be in the middle of discarding the
 		 * checkpoint.
 		 */
 		(void) printf("\nPartially discarded checkpoint "
 		    "state found:\n");
 		if (dump_opt['m'] > 3)
 			dump_leftover_checkpoint_blocks(spa);
 		return (0);
 	} else if (error != 0) {
 		(void) printf("lookup error %d when looking for "
 		    "checkpointed uberblock in MOS\n", error);
 		return (error);
 	}
 	dump_uberblock(&checkpoint, "\nCheckpointed uberblock found:\n", "\n");
 
 	if (checkpoint.ub_checkpoint_txg == 0) {
 		(void) printf("\nub_checkpoint_txg not set in checkpointed "
 		    "uberblock\n");
 		error = 3;
 	}
 
 	if (error == 0 && !dump_opt['L'])
 		verify_checkpoint_blocks(spa);
 
 	return (error);
 }
 
 static void
 mos_leaks_cb(void *arg, uint64_t start, uint64_t size)
 {
 	(void) arg;
 	for (uint64_t i = start; i < size; i++) {
 		(void) printf("MOS object %llu referenced but not allocated\n",
 		    (u_longlong_t)i);
 	}
 }
 
 static void
 mos_obj_refd(uint64_t obj)
 {
 	if (obj != 0 && mos_refd_objs != NULL)
 		range_tree_add(mos_refd_objs, obj, 1);
 }
 
 /*
  * Call on a MOS object that may already have been referenced.
  */
 static void
 mos_obj_refd_multiple(uint64_t obj)
 {
 	if (obj != 0 && mos_refd_objs != NULL &&
 	    !range_tree_contains(mos_refd_objs, obj, 1))
 		range_tree_add(mos_refd_objs, obj, 1);
 }
 
 static void
 mos_leak_vdev_top_zap(vdev_t *vd)
 {
 	uint64_t ms_flush_data_obj;
 	int error = zap_lookup(spa_meta_objset(vd->vdev_spa),
 	    vd->vdev_top_zap, VDEV_TOP_ZAP_MS_UNFLUSHED_PHYS_TXGS,
 	    sizeof (ms_flush_data_obj), 1, &ms_flush_data_obj);
 	if (error == ENOENT)
 		return;
 	ASSERT0(error);
 
 	mos_obj_refd(ms_flush_data_obj);
 }
 
 static void
 mos_leak_vdev(vdev_t *vd)
 {
 	mos_obj_refd(vd->vdev_dtl_object);
 	mos_obj_refd(vd->vdev_ms_array);
 	mos_obj_refd(vd->vdev_indirect_config.vic_births_object);
 	mos_obj_refd(vd->vdev_indirect_config.vic_mapping_object);
 	mos_obj_refd(vd->vdev_leaf_zap);
 	if (vd->vdev_checkpoint_sm != NULL)
 		mos_obj_refd(vd->vdev_checkpoint_sm->sm_object);
 	if (vd->vdev_indirect_mapping != NULL) {
 		mos_obj_refd(vd->vdev_indirect_mapping->
 		    vim_phys->vimp_counts_object);
 	}
 	if (vd->vdev_obsolete_sm != NULL)
 		mos_obj_refd(vd->vdev_obsolete_sm->sm_object);
 
 	for (uint64_t m = 0; m < vd->vdev_ms_count; m++) {
 		metaslab_t *ms = vd->vdev_ms[m];
 		mos_obj_refd(space_map_object(ms->ms_sm));
 	}
 
 	if (vd->vdev_root_zap != 0)
 		mos_obj_refd(vd->vdev_root_zap);
 
 	if (vd->vdev_top_zap != 0) {
 		mos_obj_refd(vd->vdev_top_zap);
 		mos_leak_vdev_top_zap(vd);
 	}
 
 	for (uint64_t c = 0; c < vd->vdev_children; c++) {
 		mos_leak_vdev(vd->vdev_child[c]);
 	}
 }
 
 static void
 mos_leak_log_spacemaps(spa_t *spa)
 {
 	uint64_t spacemap_zap;
 	int error = zap_lookup(spa_meta_objset(spa),
 	    DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_LOG_SPACEMAP_ZAP,
 	    sizeof (spacemap_zap), 1, &spacemap_zap);
 	if (error == ENOENT)
 		return;
 	ASSERT0(error);
 
 	mos_obj_refd(spacemap_zap);
 	for (spa_log_sm_t *sls = avl_first(&spa->spa_sm_logs_by_txg);
 	    sls; sls = AVL_NEXT(&spa->spa_sm_logs_by_txg, sls))
 		mos_obj_refd(sls->sls_sm_obj);
 }
 
 static void
 errorlog_count_refd(objset_t *mos, uint64_t errlog)
 {
 	zap_cursor_t zc;
 	zap_attribute_t za;
 	for (zap_cursor_init(&zc, mos, errlog);
 	    zap_cursor_retrieve(&zc, &za) == 0;
 	    zap_cursor_advance(&zc)) {
 		mos_obj_refd(za.za_first_integer);
 	}
 	zap_cursor_fini(&zc);
 }
 
 static int
 dump_mos_leaks(spa_t *spa)
 {
 	int rv = 0;
 	objset_t *mos = spa->spa_meta_objset;
 	dsl_pool_t *dp = spa->spa_dsl_pool;
 
 	/* Visit and mark all referenced objects in the MOS */
 
 	mos_obj_refd(DMU_POOL_DIRECTORY_OBJECT);
 	mos_obj_refd(spa->spa_pool_props_object);
 	mos_obj_refd(spa->spa_config_object);
 	mos_obj_refd(spa->spa_ddt_stat_object);
 	mos_obj_refd(spa->spa_feat_desc_obj);
 	mos_obj_refd(spa->spa_feat_enabled_txg_obj);
 	mos_obj_refd(spa->spa_feat_for_read_obj);
 	mos_obj_refd(spa->spa_feat_for_write_obj);
 	mos_obj_refd(spa->spa_history);
 	mos_obj_refd(spa->spa_errlog_last);
 	mos_obj_refd(spa->spa_errlog_scrub);
 
 	if (spa_feature_is_enabled(spa, SPA_FEATURE_HEAD_ERRLOG)) {
 		errorlog_count_refd(mos, spa->spa_errlog_last);
 		errorlog_count_refd(mos, spa->spa_errlog_scrub);
 	}
 
 	mos_obj_refd(spa->spa_all_vdev_zaps);
 	mos_obj_refd(spa->spa_dsl_pool->dp_bptree_obj);
 	mos_obj_refd(spa->spa_dsl_pool->dp_tmp_userrefs_obj);
 	mos_obj_refd(spa->spa_dsl_pool->dp_scan->scn_phys.scn_queue_obj);
 	bpobj_count_refd(&spa->spa_deferred_bpobj);
 	mos_obj_refd(dp->dp_empty_bpobj);
 	bpobj_count_refd(&dp->dp_obsolete_bpobj);
 	bpobj_count_refd(&dp->dp_free_bpobj);
 	mos_obj_refd(spa->spa_l2cache.sav_object);
 	mos_obj_refd(spa->spa_spares.sav_object);
 
 	if (spa->spa_syncing_log_sm != NULL)
 		mos_obj_refd(spa->spa_syncing_log_sm->sm_object);
 	mos_leak_log_spacemaps(spa);
 
 	mos_obj_refd(spa->spa_condensing_indirect_phys.
 	    scip_next_mapping_object);
 	mos_obj_refd(spa->spa_condensing_indirect_phys.
 	    scip_prev_obsolete_sm_object);
 	if (spa->spa_condensing_indirect_phys.scip_next_mapping_object != 0) {
 		vdev_indirect_mapping_t *vim =
 		    vdev_indirect_mapping_open(mos,
 		    spa->spa_condensing_indirect_phys.scip_next_mapping_object);
 		mos_obj_refd(vim->vim_phys->vimp_counts_object);
 		vdev_indirect_mapping_close(vim);
 	}
 	deleted_livelists_dump_mos(spa);
 
 	if (dp->dp_origin_snap != NULL) {
 		dsl_dataset_t *ds;
 
 		dsl_pool_config_enter(dp, FTAG);
 		VERIFY0(dsl_dataset_hold_obj(dp,
 		    dsl_dataset_phys(dp->dp_origin_snap)->ds_next_snap_obj,
 		    FTAG, &ds));
 		count_ds_mos_objects(ds);
 		dump_blkptr_list(&ds->ds_deadlist, "Deadlist");
 		dsl_dataset_rele(ds, FTAG);
 		dsl_pool_config_exit(dp, FTAG);
 
 		count_ds_mos_objects(dp->dp_origin_snap);
 		dump_blkptr_list(&dp->dp_origin_snap->ds_deadlist, "Deadlist");
 	}
 	count_dir_mos_objects(dp->dp_mos_dir);
 	if (dp->dp_free_dir != NULL)
 		count_dir_mos_objects(dp->dp_free_dir);
 	if (dp->dp_leak_dir != NULL)
 		count_dir_mos_objects(dp->dp_leak_dir);
 
 	mos_leak_vdev(spa->spa_root_vdev);
 
 	for (uint64_t class = 0; class < DDT_CLASSES; class++) {
 		for (uint64_t type = 0; type < DDT_TYPES; type++) {
 			for (uint64_t cksum = 0;
 			    cksum < ZIO_CHECKSUM_FUNCTIONS; cksum++) {
 				ddt_t *ddt = spa->spa_ddt[cksum];
 				mos_obj_refd(ddt->ddt_object[type][class]);
 			}
 		}
 	}
 
 	if (spa->spa_brt != NULL) {
 		brt_t *brt = spa->spa_brt;
 		for (uint64_t vdevid = 0; vdevid < brt->brt_nvdevs; vdevid++) {
 			brt_vdev_t *brtvd = &brt->brt_vdevs[vdevid];
 			if (brtvd != NULL && brtvd->bv_initiated) {
 				mos_obj_refd(brtvd->bv_mos_brtvdev);
 				mos_obj_refd(brtvd->bv_mos_entries);
 			}
 		}
 	}
 
 	/*
 	 * Visit all allocated objects and make sure they are referenced.
 	 */
 	uint64_t object = 0;
 	while (dmu_object_next(mos, &object, B_FALSE, 0) == 0) {
 		if (range_tree_contains(mos_refd_objs, object, 1)) {
 			range_tree_remove(mos_refd_objs, object, 1);
 		} else {
 			dmu_object_info_t doi;
 			const char *name;
 			VERIFY0(dmu_object_info(mos, object, &doi));
 			if (doi.doi_type & DMU_OT_NEWTYPE) {
 				dmu_object_byteswap_t bswap =
 				    DMU_OT_BYTESWAP(doi.doi_type);
 				name = dmu_ot_byteswap[bswap].ob_name;
 			} else {
 				name = dmu_ot[doi.doi_type].ot_name;
 			}
 
 			(void) printf("MOS object %llu (%s) leaked\n",
 			    (u_longlong_t)object, name);
 			rv = 2;
 		}
 	}
 	(void) range_tree_walk(mos_refd_objs, mos_leaks_cb, NULL);
 	if (!range_tree_is_empty(mos_refd_objs))
 		rv = 2;
 	range_tree_vacate(mos_refd_objs, NULL, NULL);
 	range_tree_destroy(mos_refd_objs);
 	return (rv);
 }
 
 typedef struct log_sm_obsolete_stats_arg {
 	uint64_t lsos_current_txg;
 
 	uint64_t lsos_total_entries;
 	uint64_t lsos_valid_entries;
 
 	uint64_t lsos_sm_entries;
 	uint64_t lsos_valid_sm_entries;
 } log_sm_obsolete_stats_arg_t;
 
 static int
 log_spacemap_obsolete_stats_cb(spa_t *spa, space_map_entry_t *sme,
     uint64_t txg, void *arg)
 {
 	log_sm_obsolete_stats_arg_t *lsos = arg;
 
 	uint64_t offset = sme->sme_offset;
 	uint64_t vdev_id = sme->sme_vdev;
 
 	if (lsos->lsos_current_txg == 0) {
 		/* this is the first log */
 		lsos->lsos_current_txg = txg;
 	} else if (lsos->lsos_current_txg < txg) {
 		/* we just changed log - print stats and reset */
 		(void) printf("%-8llu valid entries out of %-8llu - txg %llu\n",
 		    (u_longlong_t)lsos->lsos_valid_sm_entries,
 		    (u_longlong_t)lsos->lsos_sm_entries,
 		    (u_longlong_t)lsos->lsos_current_txg);
 		lsos->lsos_valid_sm_entries = 0;
 		lsos->lsos_sm_entries = 0;
 		lsos->lsos_current_txg = txg;
 	}
 	ASSERT3U(lsos->lsos_current_txg, ==, txg);
 
 	lsos->lsos_sm_entries++;
 	lsos->lsos_total_entries++;
 
 	vdev_t *vd = vdev_lookup_top(spa, vdev_id);
 	if (!vdev_is_concrete(vd))
 		return (0);
 
 	metaslab_t *ms = vd->vdev_ms[offset >> vd->vdev_ms_shift];
 	ASSERT(sme->sme_type == SM_ALLOC || sme->sme_type == SM_FREE);
 
 	if (txg < metaslab_unflushed_txg(ms))
 		return (0);
 	lsos->lsos_valid_sm_entries++;
 	lsos->lsos_valid_entries++;
 	return (0);
 }
 
 static void
 dump_log_spacemap_obsolete_stats(spa_t *spa)
 {
 	if (!spa_feature_is_active(spa, SPA_FEATURE_LOG_SPACEMAP))
 		return;
 
 	log_sm_obsolete_stats_arg_t lsos = {0};
 
 	(void) printf("Log Space Map Obsolete Entry Statistics:\n");
 
 	iterate_through_spacemap_logs(spa,
 	    log_spacemap_obsolete_stats_cb, &lsos);
 
 	/* print stats for latest log */
 	(void) printf("%-8llu valid entries out of %-8llu - txg %llu\n",
 	    (u_longlong_t)lsos.lsos_valid_sm_entries,
 	    (u_longlong_t)lsos.lsos_sm_entries,
 	    (u_longlong_t)lsos.lsos_current_txg);
 
 	(void) printf("%-8llu valid entries out of %-8llu - total\n\n",
 	    (u_longlong_t)lsos.lsos_valid_entries,
 	    (u_longlong_t)lsos.lsos_total_entries);
 }
 
 static void
 dump_zpool(spa_t *spa)
 {
 	dsl_pool_t *dp = spa_get_dsl(spa);
 	int rc = 0;
 
 	if (dump_opt['y']) {
 		livelist_metaslab_validate(spa);
 	}
 
 	if (dump_opt['S']) {
 		dump_simulated_ddt(spa);
 		return;
 	}
 
 	if (!dump_opt['e'] && dump_opt['C'] > 1) {
 		(void) printf("\nCached configuration:\n");
 		dump_nvlist(spa->spa_config, 8);
 	}
 
 	if (dump_opt['C'])
 		dump_config(spa);
 
 	if (dump_opt['u'])
 		dump_uberblock(&spa->spa_uberblock, "\nUberblock:\n", "\n");
 
 	if (dump_opt['D'])
 		dump_all_ddts(spa);
 
 	if (dump_opt['T'])
 		dump_brt(spa);
 
 	if (dump_opt['d'] > 2 || dump_opt['m'])
 		dump_metaslabs(spa);
 	if (dump_opt['M'])
 		dump_metaslab_groups(spa, dump_opt['M'] > 1);
 	if (dump_opt['d'] > 2 || dump_opt['m']) {
 		dump_log_spacemaps(spa);
 		dump_log_spacemap_obsolete_stats(spa);
 	}
 
 	if (dump_opt['d'] || dump_opt['i']) {
 		spa_feature_t f;
 		mos_refd_objs = range_tree_create(NULL, RANGE_SEG64, NULL, 0,
 		    0);
 		dump_objset(dp->dp_meta_objset);
 
 		if (dump_opt['d'] >= 3) {
 			dsl_pool_t *dp = spa->spa_dsl_pool;
 			dump_full_bpobj(&spa->spa_deferred_bpobj,
 			    "Deferred frees", 0);
 			if (spa_version(spa) >= SPA_VERSION_DEADLISTS) {
 				dump_full_bpobj(&dp->dp_free_bpobj,
 				    "Pool snapshot frees", 0);
 			}
 			if (bpobj_is_open(&dp->dp_obsolete_bpobj)) {
 				ASSERT(spa_feature_is_enabled(spa,
 				    SPA_FEATURE_DEVICE_REMOVAL));
 				dump_full_bpobj(&dp->dp_obsolete_bpobj,
 				    "Pool obsolete blocks", 0);
 			}
 
 			if (spa_feature_is_active(spa,
 			    SPA_FEATURE_ASYNC_DESTROY)) {
 				dump_bptree(spa->spa_meta_objset,
 				    dp->dp_bptree_obj,
 				    "Pool dataset frees");
 			}
 			dump_dtl(spa->spa_root_vdev, 0);
 		}
 
 		for (spa_feature_t f = 0; f < SPA_FEATURES; f++)
 			global_feature_count[f] = UINT64_MAX;
 		global_feature_count[SPA_FEATURE_REDACTION_BOOKMARKS] = 0;
 		global_feature_count[SPA_FEATURE_BOOKMARK_WRITTEN] = 0;
 		global_feature_count[SPA_FEATURE_LIVELIST] = 0;
 
 		(void) dmu_objset_find(spa_name(spa), dump_one_objset,
 		    NULL, DS_FIND_SNAPSHOTS | DS_FIND_CHILDREN);
 
 		if (rc == 0 && !dump_opt['L'])
 			rc = dump_mos_leaks(spa);
 
 		for (f = 0; f < SPA_FEATURES; f++) {
 			uint64_t refcount;
 
 			uint64_t *arr;
 			if (!(spa_feature_table[f].fi_flags &
 			    ZFEATURE_FLAG_PER_DATASET)) {
 				if (global_feature_count[f] == UINT64_MAX)
 					continue;
 				if (!spa_feature_is_enabled(spa, f)) {
 					ASSERT0(global_feature_count[f]);
 					continue;
 				}
 				arr = global_feature_count;
 			} else {
 				if (!spa_feature_is_enabled(spa, f)) {
 					ASSERT0(dataset_feature_count[f]);
 					continue;
 				}
 				arr = dataset_feature_count;
 			}
 			if (feature_get_refcount(spa, &spa_feature_table[f],
 			    &refcount) == ENOTSUP)
 				continue;
 			if (arr[f] != refcount) {
 				(void) printf("%s feature refcount mismatch: "
 				    "%lld consumers != %lld refcount\n",
 				    spa_feature_table[f].fi_uname,
 				    (longlong_t)arr[f], (longlong_t)refcount);
 				rc = 2;
 			} else {
 				(void) printf("Verified %s feature refcount "
 				    "of %llu is correct\n",
 				    spa_feature_table[f].fi_uname,
 				    (longlong_t)refcount);
 			}
 		}
 
 		if (rc == 0)
 			rc = verify_device_removal_feature_counts(spa);
 	}
 
 	if (rc == 0 && (dump_opt['b'] || dump_opt['c']))
 		rc = dump_block_stats(spa);
 
 	if (rc == 0)
 		rc = verify_spacemap_refcounts(spa);
 
 	if (dump_opt['s'])
 		show_pool_stats(spa);
 
 	if (dump_opt['h'])
 		dump_history(spa);
 
 	if (rc == 0)
 		rc = verify_checkpoint(spa);
 
 	if (rc != 0) {
 		dump_debug_buffer();
 		exit(rc);
 	}
 }
 
 #define	ZDB_FLAG_CHECKSUM	0x0001
 #define	ZDB_FLAG_DECOMPRESS	0x0002
 #define	ZDB_FLAG_BSWAP		0x0004
 #define	ZDB_FLAG_GBH		0x0008
 #define	ZDB_FLAG_INDIRECT	0x0010
 #define	ZDB_FLAG_RAW		0x0020
 #define	ZDB_FLAG_PRINT_BLKPTR	0x0040
 #define	ZDB_FLAG_VERBOSE	0x0080
 
 static int flagbits[256];
 static char flagbitstr[16];
 
 static void
 zdb_print_blkptr(const blkptr_t *bp, int flags)
 {
 	char blkbuf[BP_SPRINTF_LEN];
 
 	if (flags & ZDB_FLAG_BSWAP)
 		byteswap_uint64_array((void *)bp, sizeof (blkptr_t));
 
 	snprintf_blkptr(blkbuf, sizeof (blkbuf), bp);
 	(void) printf("%s\n", blkbuf);
 }
 
 static void
 zdb_dump_indirect(blkptr_t *bp, int nbps, int flags)
 {
 	int i;
 
 	for (i = 0; i < nbps; i++)
 		zdb_print_blkptr(&bp[i], flags);
 }
 
 static void
 zdb_dump_gbh(void *buf, int flags)
 {
 	zdb_dump_indirect((blkptr_t *)buf, SPA_GBH_NBLKPTRS, flags);
 }
 
 static void
 zdb_dump_block_raw(void *buf, uint64_t size, int flags)
 {
 	if (flags & ZDB_FLAG_BSWAP)
 		byteswap_uint64_array(buf, size);
 	VERIFY(write(fileno(stdout), buf, size) == size);
 }
 
 static void
 zdb_dump_block(char *label, void *buf, uint64_t size, int flags)
 {
 	uint64_t *d = (uint64_t *)buf;
 	unsigned nwords = size / sizeof (uint64_t);
 	int do_bswap = !!(flags & ZDB_FLAG_BSWAP);
 	unsigned i, j;
 	const char *hdr;
 	char *c;
 
 
 	if (do_bswap)
 		hdr = " 7 6 5 4 3 2 1 0   f e d c b a 9 8";
 	else
 		hdr = " 0 1 2 3 4 5 6 7   8 9 a b c d e f";
 
 	(void) printf("\n%s\n%6s   %s  0123456789abcdef\n", label, "", hdr);
 
 #ifdef _LITTLE_ENDIAN
 	/* correct the endianness */
 	do_bswap = !do_bswap;
 #endif
 	for (i = 0; i < nwords; i += 2) {
 		(void) printf("%06llx:  %016llx  %016llx  ",
 		    (u_longlong_t)(i * sizeof (uint64_t)),
 		    (u_longlong_t)(do_bswap ? BSWAP_64(d[i]) : d[i]),
 		    (u_longlong_t)(do_bswap ? BSWAP_64(d[i + 1]) : d[i + 1]));
 
 		c = (char *)&d[i];
 		for (j = 0; j < 2 * sizeof (uint64_t); j++)
 			(void) printf("%c", isprint(c[j]) ? c[j] : '.');
 		(void) printf("\n");
 	}
 }
 
 /*
  * There are two acceptable formats:
  *	leaf_name	  - For example: c1t0d0 or /tmp/ztest.0a
  *	child[.child]*    - For example: 0.1.1
  *
  * The second form can be used to specify arbitrary vdevs anywhere
  * in the hierarchy.  For example, in a pool with a mirror of
  * RAID-Zs, you can specify either RAID-Z vdev with 0.0 or 0.1 .
  */
 static vdev_t *
 zdb_vdev_lookup(vdev_t *vdev, const char *path)
 {
 	char *s, *p, *q;
 	unsigned i;
 
 	if (vdev == NULL)
 		return (NULL);
 
 	/* First, assume the x.x.x.x format */
 	i = strtoul(path, &s, 10);
 	if (s == path || (s && *s != '.' && *s != '\0'))
 		goto name;
 	if (i >= vdev->vdev_children)
 		return (NULL);
 
 	vdev = vdev->vdev_child[i];
 	if (s && *s == '\0')
 		return (vdev);
 	return (zdb_vdev_lookup(vdev, s+1));
 
 name:
 	for (i = 0; i < vdev->vdev_children; i++) {
 		vdev_t *vc = vdev->vdev_child[i];
 
 		if (vc->vdev_path == NULL) {
 			vc = zdb_vdev_lookup(vc, path);
 			if (vc == NULL)
 				continue;
 			else
 				return (vc);
 		}
 
 		p = strrchr(vc->vdev_path, '/');
 		p = p ? p + 1 : vc->vdev_path;
 		q = &vc->vdev_path[strlen(vc->vdev_path) - 2];
 
 		if (strcmp(vc->vdev_path, path) == 0)
 			return (vc);
 		if (strcmp(p, path) == 0)
 			return (vc);
 		if (strcmp(q, "s0") == 0 && strncmp(p, path, q - p) == 0)
 			return (vc);
 	}
 
 	return (NULL);
 }
 
 static int
 name_from_objset_id(spa_t *spa, uint64_t objset_id, char *outstr)
 {
 	dsl_dataset_t *ds;
 
 	dsl_pool_config_enter(spa->spa_dsl_pool, FTAG);
 	int error = dsl_dataset_hold_obj(spa->spa_dsl_pool, objset_id,
 	    NULL, &ds);
 	if (error != 0) {
 		(void) fprintf(stderr, "failed to hold objset %llu: %s\n",
 		    (u_longlong_t)objset_id, strerror(error));
 		dsl_pool_config_exit(spa->spa_dsl_pool, FTAG);
 		return (error);
 	}
 	dsl_dataset_name(ds, outstr);
 	dsl_dataset_rele(ds, NULL);
 	dsl_pool_config_exit(spa->spa_dsl_pool, FTAG);
 	return (0);
 }
 
 static boolean_t
 zdb_parse_block_sizes(char *sizes, uint64_t *lsize, uint64_t *psize)
 {
 	char *s0, *s1, *tmp = NULL;
 
 	if (sizes == NULL)
 		return (B_FALSE);
 
 	s0 = strtok_r(sizes, "/", &tmp);
 	if (s0 == NULL)
 		return (B_FALSE);
 	s1 = strtok_r(NULL, "/", &tmp);
 	*lsize = strtoull(s0, NULL, 16);
 	*psize = s1 ? strtoull(s1, NULL, 16) : *lsize;
 	return (*lsize >= *psize && *psize > 0);
 }
 
 #define	ZIO_COMPRESS_MASK(alg)	(1ULL << (ZIO_COMPRESS_##alg))
 
 static boolean_t
 zdb_decompress_block(abd_t *pabd, void *buf, void *lbuf, uint64_t lsize,
     uint64_t psize, int flags)
 {
 	(void) buf;
 	boolean_t exceeded = B_FALSE;
 	/*
 	 * We don't know how the data was compressed, so just try
 	 * every decompress function at every inflated blocksize.
 	 */
 	void *lbuf2 = umem_alloc(SPA_MAXBLOCKSIZE, UMEM_NOFAIL);
 	int cfuncs[ZIO_COMPRESS_FUNCTIONS] = { 0 };
 	int *cfuncp = cfuncs;
 	uint64_t maxlsize = SPA_MAXBLOCKSIZE;
 	uint64_t mask = ZIO_COMPRESS_MASK(ON) | ZIO_COMPRESS_MASK(OFF) |
 	    ZIO_COMPRESS_MASK(INHERIT) | ZIO_COMPRESS_MASK(EMPTY) |
 	    (getenv("ZDB_NO_ZLE") ? ZIO_COMPRESS_MASK(ZLE) : 0);
 	*cfuncp++ = ZIO_COMPRESS_LZ4;
 	*cfuncp++ = ZIO_COMPRESS_LZJB;
 	mask |= ZIO_COMPRESS_MASK(LZ4) | ZIO_COMPRESS_MASK(LZJB);
 	/*
 	 * Every gzip level has the same decompressor, no need to
 	 * run it 9 times per bruteforce attempt.
 	 */
 	mask |= ZIO_COMPRESS_MASK(GZIP_2) | ZIO_COMPRESS_MASK(GZIP_3);
 	mask |= ZIO_COMPRESS_MASK(GZIP_4) | ZIO_COMPRESS_MASK(GZIP_5);
 	mask |= ZIO_COMPRESS_MASK(GZIP_6) | ZIO_COMPRESS_MASK(GZIP_7);
 	mask |= ZIO_COMPRESS_MASK(GZIP_8) | ZIO_COMPRESS_MASK(GZIP_9);
 	for (int c = 0; c < ZIO_COMPRESS_FUNCTIONS; c++)
 		if (((1ULL << c) & mask) == 0)
 			*cfuncp++ = c;
 
 	/*
 	 * On the one hand, with SPA_MAXBLOCKSIZE at 16MB, this
 	 * could take a while and we should let the user know
 	 * we are not stuck.  On the other hand, printing progress
 	 * info gets old after a while.  User can specify 'v' flag
 	 * to see the progression.
 	 */
 	if (lsize == psize)
 		lsize += SPA_MINBLOCKSIZE;
 	else
 		maxlsize = lsize;
 	for (; lsize <= maxlsize; lsize += SPA_MINBLOCKSIZE) {
 		for (cfuncp = cfuncs; *cfuncp; cfuncp++) {
 			if (flags & ZDB_FLAG_VERBOSE) {
 				(void) fprintf(stderr,
 				    "Trying %05llx -> %05llx (%s)\n",
 				    (u_longlong_t)psize,
 				    (u_longlong_t)lsize,
 				    zio_compress_table[*cfuncp].\
 				    ci_name);
 			}
 
 			/*
 			 * We randomize lbuf2, and decompress to both
 			 * lbuf and lbuf2. This way, we will know if
 			 * decompression fill exactly to lsize.
 			 */
 			VERIFY0(random_get_pseudo_bytes(lbuf2, lsize));
 
 			if (zio_decompress_data(*cfuncp, pabd,
 			    lbuf, psize, lsize, NULL) == 0 &&
 			    zio_decompress_data(*cfuncp, pabd,
 			    lbuf2, psize, lsize, NULL) == 0 &&
 			    memcmp(lbuf, lbuf2, lsize) == 0)
 				break;
 		}
 		if (*cfuncp != 0)
 			break;
 	}
 	umem_free(lbuf2, SPA_MAXBLOCKSIZE);
 
 	if (lsize > maxlsize) {
 		exceeded = B_TRUE;
 	}
 	if (*cfuncp == ZIO_COMPRESS_ZLE) {
 		printf("\nZLE decompression was selected. If you "
 		    "suspect the results are wrong,\ntry avoiding ZLE "
 		    "by setting and exporting ZDB_NO_ZLE=\"true\"\n");
 	}
 
 	return (exceeded);
 }
 
 /*
  * Read a block from a pool and print it out.  The syntax of the
  * block descriptor is:
  *
  *	pool:vdev_specifier:offset:[lsize/]psize[:flags]
  *
  *	pool           - The name of the pool you wish to read from
  *	vdev_specifier - Which vdev (see comment for zdb_vdev_lookup)
  *	offset         - offset, in hex, in bytes
  *	size           - Amount of data to read, in hex, in bytes
  *	flags          - A string of characters specifying options
  *		 b: Decode a blkptr at given offset within block
  *		 c: Calculate and display checksums
  *		 d: Decompress data before dumping
  *		 e: Byteswap data before dumping
  *		 g: Display data as a gang block header
  *		 i: Display as an indirect block
  *		 r: Dump raw data to stdout
  *		 v: Verbose
  *
  */
 static void
 zdb_read_block(char *thing, spa_t *spa)
 {
 	blkptr_t blk, *bp = &blk;
 	dva_t *dva = bp->blk_dva;
 	int flags = 0;
 	uint64_t offset = 0, psize = 0, lsize = 0, blkptr_offset = 0;
 	zio_t *zio;
 	vdev_t *vd;
 	abd_t *pabd;
 	void *lbuf, *buf;
 	char *s, *p, *dup, *flagstr, *sizes, *tmp = NULL;
 	const char *vdev, *errmsg = NULL;
 	int i, error;
 	boolean_t borrowed = B_FALSE, found = B_FALSE;
 
 	dup = strdup(thing);
 	s = strtok_r(dup, ":", &tmp);
 	vdev = s ?: "";
 	s = strtok_r(NULL, ":", &tmp);
 	offset = strtoull(s ? s : "", NULL, 16);
 	sizes = strtok_r(NULL, ":", &tmp);
 	s = strtok_r(NULL, ":", &tmp);
 	flagstr = strdup(s ?: "");
 
 	if (!zdb_parse_block_sizes(sizes, &lsize, &psize))
 		errmsg = "invalid size(s)";
 	if (!IS_P2ALIGNED(psize, DEV_BSIZE) || !IS_P2ALIGNED(lsize, DEV_BSIZE))
 		errmsg = "size must be a multiple of sector size";
 	if (!IS_P2ALIGNED(offset, DEV_BSIZE))
 		errmsg = "offset must be a multiple of sector size";
 	if (errmsg) {
 		(void) printf("Invalid block specifier: %s  - %s\n",
 		    thing, errmsg);
 		goto done;
 	}
 
 	tmp = NULL;
 	for (s = strtok_r(flagstr, ":", &tmp);
 	    s != NULL;
 	    s = strtok_r(NULL, ":", &tmp)) {
 		for (i = 0; i < strlen(flagstr); i++) {
 			int bit = flagbits[(uchar_t)flagstr[i]];
 
 			if (bit == 0) {
 				(void) printf("***Ignoring flag: %c\n",
 				    (uchar_t)flagstr[i]);
 				continue;
 			}
 			found = B_TRUE;
 			flags |= bit;
 
 			p = &flagstr[i + 1];
 			if (*p != ':' && *p != '\0') {
 				int j = 0, nextbit = flagbits[(uchar_t)*p];
 				char *end, offstr[8] = { 0 };
 				if ((bit == ZDB_FLAG_PRINT_BLKPTR) &&
 				    (nextbit == 0)) {
 					/* look ahead to isolate the offset */
 					while (nextbit == 0 &&
 					    strchr(flagbitstr, *p) == NULL) {
 						offstr[j] = *p;
 						j++;
 						if (i + j > strlen(flagstr))
 							break;
 						p++;
 						nextbit = flagbits[(uchar_t)*p];
 					}
 					blkptr_offset = strtoull(offstr, &end,
 					    16);
 					i += j;
 				} else if (nextbit == 0) {
 					(void) printf("***Ignoring flag arg:"
 					    " '%c'\n", (uchar_t)*p);
 				}
 			}
 		}
 	}
 	if (blkptr_offset % sizeof (blkptr_t)) {
 		printf("Block pointer offset 0x%llx "
 		    "must be divisible by 0x%x\n",
 		    (longlong_t)blkptr_offset, (int)sizeof (blkptr_t));
 		goto done;
 	}
 	if (found == B_FALSE && strlen(flagstr) > 0) {
 		printf("Invalid flag arg: '%s'\n", flagstr);
 		goto done;
 	}
 
 	vd = zdb_vdev_lookup(spa->spa_root_vdev, vdev);
 	if (vd == NULL) {
 		(void) printf("***Invalid vdev: %s\n", vdev);
 		goto done;
 	} else {
 		if (vd->vdev_path)
 			(void) fprintf(stderr, "Found vdev: %s\n",
 			    vd->vdev_path);
 		else
 			(void) fprintf(stderr, "Found vdev type: %s\n",
 			    vd->vdev_ops->vdev_op_type);
 	}
 
 	pabd = abd_alloc_for_io(SPA_MAXBLOCKSIZE, B_FALSE);
 	lbuf = umem_alloc(SPA_MAXBLOCKSIZE, UMEM_NOFAIL);
 
 	BP_ZERO(bp);
 
 	DVA_SET_VDEV(&dva[0], vd->vdev_id);
 	DVA_SET_OFFSET(&dva[0], offset);
 	DVA_SET_GANG(&dva[0], !!(flags & ZDB_FLAG_GBH));
 	DVA_SET_ASIZE(&dva[0], vdev_psize_to_asize(vd, psize));
 
 	BP_SET_BIRTH(bp, TXG_INITIAL, TXG_INITIAL);
 
 	BP_SET_LSIZE(bp, lsize);
 	BP_SET_PSIZE(bp, psize);
 	BP_SET_COMPRESS(bp, ZIO_COMPRESS_OFF);
 	BP_SET_CHECKSUM(bp, ZIO_CHECKSUM_OFF);
 	BP_SET_TYPE(bp, DMU_OT_NONE);
 	BP_SET_LEVEL(bp, 0);
 	BP_SET_DEDUP(bp, 0);
 	BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER);
 
 	spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
 	zio = zio_root(spa, NULL, NULL, 0);
 
 	if (vd == vd->vdev_top) {
 		/*
 		 * Treat this as a normal block read.
 		 */
 		zio_nowait(zio_read(zio, spa, bp, pabd, psize, NULL, NULL,
 		    ZIO_PRIORITY_SYNC_READ,
 		    ZIO_FLAG_CANFAIL | ZIO_FLAG_RAW, NULL));
 	} else {
 		/*
 		 * Treat this as a vdev child I/O.
 		 */
 		zio_nowait(zio_vdev_child_io(zio, bp, vd, offset, pabd,
 		    psize, ZIO_TYPE_READ, ZIO_PRIORITY_SYNC_READ,
 		    ZIO_FLAG_DONT_PROPAGATE | ZIO_FLAG_DONT_RETRY |
 		    ZIO_FLAG_CANFAIL | ZIO_FLAG_RAW | ZIO_FLAG_OPTIONAL,
 		    NULL, NULL));
 	}
 
 	error = zio_wait(zio);
 	spa_config_exit(spa, SCL_STATE, FTAG);
 
 	if (error) {
 		(void) printf("Read of %s failed, error: %d\n", thing, error);
 		goto out;
 	}
 
 	uint64_t orig_lsize = lsize;
 	buf = lbuf;
 	if (flags & ZDB_FLAG_DECOMPRESS) {
 		boolean_t failed = zdb_decompress_block(pabd, buf, lbuf,
 		    lsize, psize, flags);
 		if (failed) {
 			(void) printf("Decompress of %s failed\n", thing);
 			goto out;
 		}
 	} else {
 		buf = abd_borrow_buf_copy(pabd, lsize);
 		borrowed = B_TRUE;
 	}
 	/*
 	 * Try to detect invalid block pointer.  If invalid, try
 	 * decompressing.
 	 */
 	if ((flags & ZDB_FLAG_PRINT_BLKPTR || flags & ZDB_FLAG_INDIRECT) &&
 	    !(flags & ZDB_FLAG_DECOMPRESS)) {
 		const blkptr_t *b = (const blkptr_t *)(void *)
 		    ((uintptr_t)buf + (uintptr_t)blkptr_offset);
 		if (zfs_blkptr_verify(spa, b,
 		    BLK_CONFIG_NEEDED, BLK_VERIFY_ONLY) == B_FALSE) {
 			abd_return_buf_copy(pabd, buf, lsize);
 			borrowed = B_FALSE;
 			buf = lbuf;
 			boolean_t failed = zdb_decompress_block(pabd, buf,
 			    lbuf, lsize, psize, flags);
 			b = (const blkptr_t *)(void *)
 			    ((uintptr_t)buf + (uintptr_t)blkptr_offset);
 			if (failed || zfs_blkptr_verify(spa, b,
 			    BLK_CONFIG_NEEDED, BLK_VERIFY_LOG) == B_FALSE) {
 				printf("invalid block pointer at this DVA\n");
 				goto out;
 			}
 		}
 	}
 
 	if (flags & ZDB_FLAG_PRINT_BLKPTR)
 		zdb_print_blkptr((blkptr_t *)(void *)
 		    ((uintptr_t)buf + (uintptr_t)blkptr_offset), flags);
 	else if (flags & ZDB_FLAG_RAW)
 		zdb_dump_block_raw(buf, lsize, flags);
 	else if (flags & ZDB_FLAG_INDIRECT)
 		zdb_dump_indirect((blkptr_t *)buf,
 		    orig_lsize / sizeof (blkptr_t), flags);
 	else if (flags & ZDB_FLAG_GBH)
 		zdb_dump_gbh(buf, flags);
 	else
 		zdb_dump_block(thing, buf, lsize, flags);
 
 	/*
 	 * If :c was specified, iterate through the checksum table to
 	 * calculate and display each checksum for our specified
 	 * DVA and length.
 	 */
 	if ((flags & ZDB_FLAG_CHECKSUM) && !(flags & ZDB_FLAG_RAW) &&
 	    !(flags & ZDB_FLAG_GBH)) {
 		zio_t *czio;
 		(void) printf("\n");
 		for (enum zio_checksum ck = ZIO_CHECKSUM_LABEL;
 		    ck < ZIO_CHECKSUM_FUNCTIONS; ck++) {
 
 			if ((zio_checksum_table[ck].ci_flags &
 			    ZCHECKSUM_FLAG_EMBEDDED) ||
 			    ck == ZIO_CHECKSUM_NOPARITY) {
 				continue;
 			}
 			BP_SET_CHECKSUM(bp, ck);
 			spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
 			czio = zio_root(spa, NULL, NULL, ZIO_FLAG_CANFAIL);
 			czio->io_bp = bp;
 
 			if (vd == vd->vdev_top) {
 				zio_nowait(zio_read(czio, spa, bp, pabd, psize,
 				    NULL, NULL,
 				    ZIO_PRIORITY_SYNC_READ,
 				    ZIO_FLAG_CANFAIL | ZIO_FLAG_RAW |
 				    ZIO_FLAG_DONT_RETRY, NULL));
 			} else {
 				zio_nowait(zio_vdev_child_io(czio, bp, vd,
 				    offset, pabd, psize, ZIO_TYPE_READ,
 				    ZIO_PRIORITY_SYNC_READ,
 				    ZIO_FLAG_DONT_PROPAGATE |
 				    ZIO_FLAG_DONT_RETRY |
 				    ZIO_FLAG_CANFAIL | ZIO_FLAG_RAW |
 				    ZIO_FLAG_SPECULATIVE |
 				    ZIO_FLAG_OPTIONAL, NULL, NULL));
 			}
 			error = zio_wait(czio);
 			if (error == 0 || error == ECKSUM) {
 				zio_t *ck_zio = zio_root(spa, NULL, NULL, 0);
 				ck_zio->io_offset =
 				    DVA_GET_OFFSET(&bp->blk_dva[0]);
 				ck_zio->io_bp = bp;
 				zio_checksum_compute(ck_zio, ck, pabd, lsize);
 				printf(
 				    "%12s\t"
 				    "cksum=%016llx:%016llx:%016llx:%016llx\n",
 				    zio_checksum_table[ck].ci_name,
 				    (u_longlong_t)bp->blk_cksum.zc_word[0],
 				    (u_longlong_t)bp->blk_cksum.zc_word[1],
 				    (u_longlong_t)bp->blk_cksum.zc_word[2],
 				    (u_longlong_t)bp->blk_cksum.zc_word[3]);
 				zio_wait(ck_zio);
 			} else {
 				printf("error %d reading block\n", error);
 			}
 			spa_config_exit(spa, SCL_STATE, FTAG);
 		}
 	}
 
 	if (borrowed)
 		abd_return_buf_copy(pabd, buf, lsize);
 
 out:
 	abd_free(pabd);
 	umem_free(lbuf, SPA_MAXBLOCKSIZE);
 done:
 	free(flagstr);
 	free(dup);
 }
 
 static void
 zdb_embedded_block(char *thing)
 {
 	blkptr_t bp = {{{{0}}}};
 	unsigned long long *words = (void *)&bp;
 	char *buf;
 	int err;
 
 	err = sscanf(thing, "%llx:%llx:%llx:%llx:%llx:%llx:%llx:%llx:"
 	    "%llx:%llx:%llx:%llx:%llx:%llx:%llx:%llx",
 	    words + 0, words + 1, words + 2, words + 3,
 	    words + 4, words + 5, words + 6, words + 7,
 	    words + 8, words + 9, words + 10, words + 11,
 	    words + 12, words + 13, words + 14, words + 15);
 	if (err != 16) {
 		(void) fprintf(stderr, "invalid input format\n");
 		exit(1);
 	}
 	ASSERT3U(BPE_GET_LSIZE(&bp), <=, SPA_MAXBLOCKSIZE);
 	buf = malloc(SPA_MAXBLOCKSIZE);
 	if (buf == NULL) {
 		(void) fprintf(stderr, "out of memory\n");
 		exit(1);
 	}
 	err = decode_embedded_bp(&bp, buf, BPE_GET_LSIZE(&bp));
 	if (err != 0) {
 		(void) fprintf(stderr, "decode failed: %u\n", err);
 		exit(1);
 	}
 	zdb_dump_block_raw(buf, BPE_GET_LSIZE(&bp), 0);
 	free(buf);
 }
 
 /* check for valid hex or decimal numeric string */
 static boolean_t
 zdb_numeric(char *str)
 {
 	int i = 0;
 
 	if (strlen(str) == 0)
 		return (B_FALSE);
 	if (strncmp(str, "0x", 2) == 0 || strncmp(str, "0X", 2) == 0)
 		i = 2;
 	for (; i < strlen(str); i++) {
 		if (!isxdigit(str[i]))
 			return (B_FALSE);
 	}
 	return (B_TRUE);
 }
 
 int
 main(int argc, char **argv)
 {
 	int c;
 	spa_t *spa = NULL;
 	objset_t *os = NULL;
 	int dump_all = 1;
 	int verbose = 0;
 	int error = 0;
 	char **searchdirs = NULL;
 	int nsearch = 0;
 	char *target, *target_pool, dsname[ZFS_MAX_DATASET_NAME_LEN];
 	nvlist_t *policy = NULL;
 	uint64_t max_txg = UINT64_MAX;
 	int64_t objset_id = -1;
 	uint64_t object;
 	int flags = ZFS_IMPORT_MISSING_LOG;
 	int rewind = ZPOOL_NEVER_REWIND;
 	char *spa_config_path_env, *objset_str;
 	boolean_t target_is_spa = B_TRUE, dataset_lookup = B_FALSE;
 	nvlist_t *cfg = NULL;
 	struct sigaction action;
 
 	dprintf_setup(&argc, argv);
 
 	/*
 	 * Set up signal handlers, so if we crash due to bad on-disk data we
 	 * can get more info. Unlike ztest, we don't bail out if we can't set
 	 * up signal handlers, because zdb is very useful without them.
 	 */
 	action.sa_handler = sig_handler;
 	sigemptyset(&action.sa_mask);
 	action.sa_flags = 0;
 	if (sigaction(SIGSEGV, &action, NULL) < 0) {
 		(void) fprintf(stderr, "zdb: cannot catch SIGSEGV: %s\n",
 		    strerror(errno));
 	}
 	if (sigaction(SIGABRT, &action, NULL) < 0) {
 		(void) fprintf(stderr, "zdb: cannot catch SIGABRT: %s\n",
 		    strerror(errno));
 	}
 
 	/*
 	 * If there is an environment variable SPA_CONFIG_PATH it overrides
 	 * default spa_config_path setting. If -U flag is specified it will
 	 * override this environment variable settings once again.
 	 */
 	spa_config_path_env = getenv("SPA_CONFIG_PATH");
 	if (spa_config_path_env != NULL)
 		spa_config_path = spa_config_path_env;
 
 	/*
 	 * For performance reasons, we set this tunable down. We do so before
 	 * the arg parsing section so that the user can override this value if
 	 * they choose.
 	 */
 	zfs_btree_verify_intensity = 3;
 
 	struct option long_options[] = {
 		{"ignore-assertions",	no_argument,		NULL, 'A'},
 		{"block-stats",		no_argument,		NULL, 'b'},
 		{"backup",		no_argument,		NULL, 'B'},
 		{"checksum",		no_argument,		NULL, 'c'},
 		{"config",		no_argument,		NULL, 'C'},
 		{"datasets",		no_argument,		NULL, 'd'},
 		{"dedup-stats",		no_argument,		NULL, 'D'},
 		{"exported",		no_argument,		NULL, 'e'},
 		{"embedded-block-pointer",	no_argument,	NULL, 'E'},
 		{"automatic-rewind",	no_argument,		NULL, 'F'},
 		{"dump-debug-msg",	no_argument,		NULL, 'G'},
 		{"history",		no_argument,		NULL, 'h'},
 		{"intent-logs",		no_argument,		NULL, 'i'},
 		{"inflight",		required_argument,	NULL, 'I'},
 		{"checkpointed-state",	no_argument,		NULL, 'k'},
 		{"key",			required_argument,	NULL, 'K'},
 		{"label",		no_argument,		NULL, 'l'},
 		{"disable-leak-tracking",	no_argument,	NULL, 'L'},
 		{"metaslabs",		no_argument,		NULL, 'm'},
 		{"metaslab-groups",	no_argument,		NULL, 'M'},
 		{"numeric",		no_argument,		NULL, 'N'},
 		{"option",		required_argument,	NULL, 'o'},
 		{"object-lookups",	no_argument,		NULL, 'O'},
 		{"path",		required_argument,	NULL, 'p'},
 		{"parseable",		no_argument,		NULL, 'P'},
 		{"skip-label",		no_argument,		NULL, 'q'},
 		{"copy-object",		no_argument,		NULL, 'r'},
 		{"read-block",		no_argument,		NULL, 'R'},
 		{"io-stats",		no_argument,		NULL, 's'},
 		{"simulate-dedup",	no_argument,		NULL, 'S'},
 		{"txg",			required_argument,	NULL, 't'},
 		{"brt-stats",		no_argument,		NULL, 'T'},
 		{"uberblock",		no_argument,		NULL, 'u'},
 		{"cachefile",		required_argument,	NULL, 'U'},
 		{"verbose",		no_argument,		NULL, 'v'},
 		{"verbatim",		no_argument,		NULL, 'V'},
 		{"dump-blocks",		required_argument,	NULL, 'x'},
 		{"extreme-rewind",	no_argument,		NULL, 'X'},
 		{"all-reconstruction",	no_argument,		NULL, 'Y'},
 		{"livelist",		no_argument,		NULL, 'y'},
 		{"zstd-headers",	no_argument,		NULL, 'Z'},
 		{0, 0, 0, 0}
 	};
 
 	while ((c = getopt_long(argc, argv,
 	    "AbBcCdDeEFGhiI:kK:lLmMNo:Op:PqrRsSt:TuU:vVx:XYyZ",
 	    long_options, NULL)) != -1) {
 		switch (c) {
 		case 'b':
 		case 'B':
 		case 'c':
 		case 'C':
 		case 'd':
 		case 'D':
 		case 'E':
 		case 'G':
 		case 'h':
 		case 'i':
 		case 'l':
 		case 'm':
 		case 'M':
 		case 'N':
 		case 'O':
 		case 'r':
 		case 'R':
 		case 's':
 		case 'S':
 		case 'T':
 		case 'u':
 		case 'y':
 		case 'Z':
 			dump_opt[c]++;
 			dump_all = 0;
 			break;
 		case 'A':
 		case 'e':
 		case 'F':
 		case 'k':
 		case 'L':
 		case 'P':
 		case 'q':
 		case 'X':
 			dump_opt[c]++;
 			break;
 		case 'Y':
 			zfs_reconstruct_indirect_combinations_max = INT_MAX;
 			zfs_deadman_enabled = 0;
 			break;
 		/* NB: Sort single match options below. */
 		case 'I':
 			max_inflight_bytes = strtoull(optarg, NULL, 0);
 			if (max_inflight_bytes == 0) {
 				(void) fprintf(stderr, "maximum number "
 				    "of inflight bytes must be greater "
 				    "than 0\n");
 				usage();
 			}
 			break;
 		case 'K':
 			dump_opt[c]++;
 			key_material = strdup(optarg);
 			/* redact key material in process table */
 			while (*optarg != '\0') { *optarg++ = '*'; }
 			break;
 		case 'o':
 			error = set_global_var(optarg);
 			if (error != 0)
 				usage();
 			break;
 		case 'p':
 			if (searchdirs == NULL) {
 				searchdirs = umem_alloc(sizeof (char *),
 				    UMEM_NOFAIL);
 			} else {
 				char **tmp = umem_alloc((nsearch + 1) *
 				    sizeof (char *), UMEM_NOFAIL);
 				memcpy(tmp, searchdirs, nsearch *
 				    sizeof (char *));
 				umem_free(searchdirs,
 				    nsearch * sizeof (char *));
 				searchdirs = tmp;
 			}
 			searchdirs[nsearch++] = optarg;
 			break;
 		case 't':
 			max_txg = strtoull(optarg, NULL, 0);
 			if (max_txg < TXG_INITIAL) {
 				(void) fprintf(stderr, "incorrect txg "
 				    "specified: %s\n", optarg);
 				usage();
 			}
 			break;
 		case 'U':
 			spa_config_path = optarg;
 			if (spa_config_path[0] != '/') {
 				(void) fprintf(stderr,
 				    "cachefile must be an absolute path "
 				    "(i.e. start with a slash)\n");
 				usage();
 			}
 			break;
 		case 'v':
 			verbose++;
 			break;
 		case 'V':
 			flags = ZFS_IMPORT_VERBATIM;
 			break;
 		case 'x':
 			vn_dumpdir = optarg;
 			break;
 		default:
 			usage();
 			break;
 		}
 	}
 
 	if (!dump_opt['e'] && searchdirs != NULL) {
 		(void) fprintf(stderr, "-p option requires use of -e\n");
 		usage();
 	}
 #if defined(_LP64)
 	/*
 	 * ZDB does not typically re-read blocks; therefore limit the ARC
 	 * to 256 MB, which can be used entirely for metadata.
 	 */
 	zfs_arc_min = 2ULL << SPA_MAXBLOCKSHIFT;
 	zfs_arc_max = 256 * 1024 * 1024;
 #endif
 
 	/*
 	 * "zdb -c" uses checksum-verifying scrub i/os which are async reads.
 	 * "zdb -b" uses traversal prefetch which uses async reads.
 	 * For good performance, let several of them be active at once.
 	 */
 	zfs_vdev_async_read_max_active = 10;
 
 	/*
 	 * Disable reference tracking for better performance.
 	 */
 	reference_tracking_enable = B_FALSE;
 
 	/*
 	 * Do not fail spa_load when spa_load_verify fails. This is needed
 	 * to load non-idle pools.
 	 */
 	spa_load_verify_dryrun = B_TRUE;
 
 	/*
 	 * ZDB should have ability to read spacemaps.
 	 */
 	spa_mode_readable_spacemaps = B_TRUE;
 
 	kernel_init(SPA_MODE_READ);
 
 	if (dump_all)
 		verbose = MAX(verbose, 1);
 
 	for (c = 0; c < 256; c++) {
 		if (dump_all && strchr("ABeEFkKlLNOPrRSXy", c) == NULL)
 			dump_opt[c] = 1;
 		if (dump_opt[c])
 			dump_opt[c] += verbose;
 	}
 
 	libspl_set_assert_ok((dump_opt['A'] == 1) || (dump_opt['A'] > 2));
 	zfs_recover = (dump_opt['A'] > 1);
 
 	argc -= optind;
 	argv += optind;
 	if (argc < 2 && dump_opt['R'])
 		usage();
 
 	if (dump_opt['E']) {
 		if (argc != 1)
 			usage();
 		zdb_embedded_block(argv[0]);
 		return (0);
 	}
 
 	if (argc < 1) {
 		if (!dump_opt['e'] && dump_opt['C']) {
 			dump_cachefile(spa_config_path);
 			return (0);
 		}
 		usage();
 	}
 
 	if (dump_opt['l'])
 		return (dump_label(argv[0]));
 
 	if (dump_opt['X'] || dump_opt['F'])
 		rewind = ZPOOL_DO_REWIND |
 		    (dump_opt['X'] ? ZPOOL_EXTREME_REWIND : 0);
 
 	/* -N implies -d */
 	if (dump_opt['N'] && dump_opt['d'] == 0)
 		dump_opt['d'] = dump_opt['N'];
 
 	if (nvlist_alloc(&policy, NV_UNIQUE_NAME_TYPE, 0) != 0 ||
 	    nvlist_add_uint64(policy, ZPOOL_LOAD_REQUEST_TXG, max_txg) != 0 ||
 	    nvlist_add_uint32(policy, ZPOOL_LOAD_REWIND_POLICY, rewind) != 0)
 		fatal("internal error: %s", strerror(ENOMEM));
 
 	error = 0;
 	target = argv[0];
 
 	if (strpbrk(target, "/@") != NULL) {
 		size_t targetlen;
 
 		target_pool = strdup(target);
 		*strpbrk(target_pool, "/@") = '\0';
 
 		target_is_spa = B_FALSE;
 		targetlen = strlen(target);
 		if (targetlen && target[targetlen - 1] == '/')
 			target[targetlen - 1] = '\0';
 
 		/*
 		 * See if an objset ID was supplied (-d <pool>/<objset ID>).
 		 * To disambiguate tank/100, consider the 100 as objsetID
 		 * if -N was given, otherwise 100 is an objsetID iff
 		 * tank/100 as a named dataset fails on lookup.
 		 */
 		objset_str = strchr(target, '/');
 		if (objset_str && strlen(objset_str) > 1 &&
 		    zdb_numeric(objset_str + 1)) {
 			char *endptr;
 			errno = 0;
 			objset_str++;
 			objset_id = strtoull(objset_str, &endptr, 0);
 			/* dataset 0 is the same as opening the pool */
 			if (errno == 0 && endptr != objset_str &&
 			    objset_id != 0) {
 				if (dump_opt['N'])
 					dataset_lookup = B_TRUE;
 			}
 			/* normal dataset name not an objset ID */
 			if (endptr == objset_str) {
 				objset_id = -1;
 			}
 		} else if (objset_str && !zdb_numeric(objset_str + 1) &&
 		    dump_opt['N']) {
 			printf("Supply a numeric objset ID with -N\n");
 			exit(1);
 		}
 	} else {
 		target_pool = target;
 	}
 
 	if (dump_opt['e']) {
 		importargs_t args = { 0 };
 
 		args.paths = nsearch;
 		args.path = searchdirs;
 		args.can_be_active = B_TRUE;
 
 		libpc_handle_t lpch = {
 			.lpc_lib_handle = NULL,
 			.lpc_ops = &libzpool_config_ops,
 			.lpc_printerr = B_TRUE
 		};
 		error = zpool_find_config(&lpch, target_pool, &cfg, &args);
 
 		if (error == 0) {
 
 			if (nvlist_add_nvlist(cfg,
 			    ZPOOL_LOAD_POLICY, policy) != 0) {
 				fatal("can't open '%s': %s",
 				    target, strerror(ENOMEM));
 			}
 
 			if (dump_opt['C'] > 1) {
 				(void) printf("\nConfiguration for import:\n");
 				dump_nvlist(cfg, 8);
 			}
 
 			/*
 			 * Disable the activity check to allow examination of
 			 * active pools.
 			 */
 			error = spa_import(target_pool, cfg, NULL,
 			    flags | ZFS_IMPORT_SKIP_MMP);
 		}
 	}
 
 	if (searchdirs != NULL) {
 		umem_free(searchdirs, nsearch * sizeof (char *));
 		searchdirs = NULL;
 	}
 
 	/*
 	 * We need to make sure to process -O option or call
 	 * dump_path after the -e option has been processed,
 	 * which imports the pool to the namespace if it's
 	 * not in the cachefile.
 	 */
 	if (dump_opt['O']) {
 		if (argc != 2)
 			usage();
 		dump_opt['v'] = verbose + 3;
 		return (dump_path(argv[0], argv[1], NULL));
 	}
 
 	if (dump_opt['r']) {
 		target_is_spa = B_FALSE;
 		if (argc != 3)
 			usage();
 		dump_opt['v'] = verbose;
 		error = dump_path(argv[0], argv[1], &object);
 		if (error != 0)
 			fatal("internal error: %s", strerror(error));
 	}
 
 	/*
 	 * import_checkpointed_state makes the assumption that the
 	 * target pool that we pass it is already part of the spa
 	 * namespace. Because of that we need to make sure to call
 	 * it always after the -e option has been processed, which
 	 * imports the pool to the namespace if it's not in the
 	 * cachefile.
 	 */
 	char *checkpoint_pool = NULL;
 	char *checkpoint_target = NULL;
 	if (dump_opt['k']) {
 		checkpoint_pool = import_checkpointed_state(target, cfg,
 		    &checkpoint_target);
 
 		if (checkpoint_target != NULL)
 			target = checkpoint_target;
 	}
 
 	if (cfg != NULL) {
 		nvlist_free(cfg);
 		cfg = NULL;
 	}
 
 	if (target_pool != target)
 		free(target_pool);
 
 	if (error == 0) {
 		if (dump_opt['k'] && (target_is_spa || dump_opt['R'])) {
 			ASSERT(checkpoint_pool != NULL);
 			ASSERT(checkpoint_target == NULL);
 
 			error = spa_open(checkpoint_pool, &spa, FTAG);
 			if (error != 0) {
 				fatal("Tried to open pool \"%s\" but "
 				    "spa_open() failed with error %d\n",
 				    checkpoint_pool, error);
 			}
 
 		} else if (target_is_spa || dump_opt['R'] || dump_opt['B'] ||
 		    objset_id == 0) {
 			zdb_set_skip_mmp(target);
 			error = spa_open_rewind(target, &spa, FTAG, policy,
 			    NULL);
 			if (error) {
 				/*
 				 * If we're missing the log device then
 				 * try opening the pool after clearing the
 				 * log state.
 				 */
 				mutex_enter(&spa_namespace_lock);
 				if ((spa = spa_lookup(target)) != NULL &&
 				    spa->spa_log_state == SPA_LOG_MISSING) {
 					spa->spa_log_state = SPA_LOG_CLEAR;
 					error = 0;
 				}
 				mutex_exit(&spa_namespace_lock);
 
 				if (!error) {
 					error = spa_open_rewind(target, &spa,
 					    FTAG, policy, NULL);
 				}
 			}
 		} else if (strpbrk(target, "#") != NULL) {
 			dsl_pool_t *dp;
 			error = dsl_pool_hold(target, FTAG, &dp);
 			if (error != 0) {
 				fatal("can't dump '%s': %s", target,
 				    strerror(error));
 			}
 			error = dump_bookmark(dp, target, B_TRUE, verbose > 1);
 			dsl_pool_rele(dp, FTAG);
 			if (error != 0) {
 				fatal("can't dump '%s': %s", target,
 				    strerror(error));
 			}
 			return (error);
 		} else {
 			target_pool = strdup(target);
 			if (strpbrk(target, "/@") != NULL)
 				*strpbrk(target_pool, "/@") = '\0';
 
 			zdb_set_skip_mmp(target);
 			/*
 			 * If -N was supplied, the user has indicated that
 			 * zdb -d <pool>/<objsetID> is in effect.  Otherwise
 			 * we first assume that the dataset string is the
 			 * dataset name.  If dmu_objset_hold fails with the
 			 * dataset string, and we have an objset_id, retry the
 			 * lookup with the objsetID.
 			 */
 			boolean_t retry = B_TRUE;
 retry_lookup:
 			if (dataset_lookup == B_TRUE) {
 				/*
 				 * Use the supplied id to get the name
 				 * for open_objset.
 				 */
 				error = spa_open(target_pool, &spa, FTAG);
 				if (error == 0) {
 					error = name_from_objset_id(spa,
 					    objset_id, dsname);
 					spa_close(spa, FTAG);
 					if (error == 0)
 						target = dsname;
 				}
 			}
 			if (error == 0) {
 				if (objset_id > 0 && retry) {
 					int err = dmu_objset_hold(target, FTAG,
 					    &os);
 					if (err) {
 						dataset_lookup = B_TRUE;
 						retry = B_FALSE;
 						goto retry_lookup;
 					} else {
 						dmu_objset_rele(os, FTAG);
 					}
 				}
 				error = open_objset(target, FTAG, &os);
 			}
 			if (error == 0)
 				spa = dmu_objset_spa(os);
 			free(target_pool);
 		}
 	}
 	nvlist_free(policy);
 
 	if (error)
 		fatal("can't open '%s': %s", target, strerror(error));
 
 	/*
 	 * Set the pool failure mode to panic in order to prevent the pool
 	 * from suspending.  A suspended I/O will have no way to resume and
 	 * can prevent the zdb(8) command from terminating as expected.
 	 */
 	if (spa != NULL)
 		spa->spa_failmode = ZIO_FAILURE_MODE_PANIC;
 
 	argv++;
 	argc--;
 	if (dump_opt['r']) {
 		error = zdb_copy_object(os, object, argv[1]);
 	} else if (!dump_opt['R']) {
 		flagbits['d'] = ZOR_FLAG_DIRECTORY;
 		flagbits['f'] = ZOR_FLAG_PLAIN_FILE;
 		flagbits['m'] = ZOR_FLAG_SPACE_MAP;
 		flagbits['z'] = ZOR_FLAG_ZAP;
 		flagbits['A'] = ZOR_FLAG_ALL_TYPES;
 
 		if (argc > 0 && dump_opt['d']) {
 			zopt_object_args = argc;
 			zopt_object_ranges = calloc(zopt_object_args,
 			    sizeof (zopt_object_range_t));
 			for (unsigned i = 0; i < zopt_object_args; i++) {
 				int err;
 				const char *msg = NULL;
 
 				err = parse_object_range(argv[i],
 				    &zopt_object_ranges[i], &msg);
 				if (err != 0)
 					fatal("Bad object or range: '%s': %s\n",
 					    argv[i], msg ?: "");
 			}
 		} else if (argc > 0 && dump_opt['m']) {
 			zopt_metaslab_args = argc;
 			zopt_metaslab = calloc(zopt_metaslab_args,
 			    sizeof (uint64_t));
 			for (unsigned i = 0; i < zopt_metaslab_args; i++) {
 				errno = 0;
 				zopt_metaslab[i] = strtoull(argv[i], NULL, 0);
 				if (zopt_metaslab[i] == 0 && errno != 0)
 					fatal("bad number %s: %s", argv[i],
 					    strerror(errno));
 			}
 		}
 		if (dump_opt['B']) {
 			dump_backup(target, objset_id,
 			    argc > 0 ? argv[0] : NULL);
 		} else if (os != NULL) {
 			dump_objset(os);
 		} else if (zopt_object_args > 0 && !dump_opt['m']) {
 			dump_objset(spa->spa_meta_objset);
 		} else {
 			dump_zpool(spa);
 		}
 	} else {
 		flagbits['b'] = ZDB_FLAG_PRINT_BLKPTR;
 		flagbits['c'] = ZDB_FLAG_CHECKSUM;
 		flagbits['d'] = ZDB_FLAG_DECOMPRESS;
 		flagbits['e'] = ZDB_FLAG_BSWAP;
 		flagbits['g'] = ZDB_FLAG_GBH;
 		flagbits['i'] = ZDB_FLAG_INDIRECT;
 		flagbits['r'] = ZDB_FLAG_RAW;
 		flagbits['v'] = ZDB_FLAG_VERBOSE;
 
 		for (int i = 0; i < argc; i++)
 			zdb_read_block(argv[i], spa);
 	}
 
 	if (dump_opt['k']) {
 		free(checkpoint_pool);
 		if (!target_is_spa)
 			free(checkpoint_target);
 	}
 
 	if (os != NULL) {
 		close_objset(os, FTAG);
 	} else {
 		spa_close(spa, FTAG);
 	}
 
 	fuid_table_destroy();
 
 	dump_debug_buffer();
 
 	kernel_fini();
 
 	return (error);
 }