1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2011, 2016 by Delphix. All rights reserved.
24 * Copyright (c) 2014 Integros [integros.com]
25 * Copyright (c) 2017 Datto Inc.
26 */
27
28#include <sys/bpobj.h>
29#include <sys/zfs_context.h>
30#include <sys/refcount.h>
31#include <sys/dsl_pool.h>
32#include <sys/zfeature.h>
33#include <sys/zap.h>
34
35/*
36 * Return an empty bpobj, preferably the empty dummy one (dp_empty_bpobj).
37 */
38uint64_t
39bpobj_alloc_empty(objset_t *os, int blocksize, dmu_tx_t *tx)
40{
41	spa_t *spa = dmu_objset_spa(os);
42	dsl_pool_t *dp = dmu_objset_pool(os);
43
44	if (spa_feature_is_enabled(spa, SPA_FEATURE_EMPTY_BPOBJ)) {
45		if (!spa_feature_is_active(spa, SPA_FEATURE_EMPTY_BPOBJ)) {
46			ASSERT0(dp->dp_empty_bpobj);
47			dp->dp_empty_bpobj =
48			    bpobj_alloc(os, SPA_OLD_MAXBLOCKSIZE, tx);
49			VERIFY(zap_add(os,
50			    DMU_POOL_DIRECTORY_OBJECT,
51			    DMU_POOL_EMPTY_BPOBJ, sizeof (uint64_t), 1,
52			    &dp->dp_empty_bpobj, tx) == 0);
53		}
54		spa_feature_incr(spa, SPA_FEATURE_EMPTY_BPOBJ, tx);
55		ASSERT(dp->dp_empty_bpobj != 0);
56		return (dp->dp_empty_bpobj);
57	} else {
58		return (bpobj_alloc(os, blocksize, tx));
59	}
60}
61
62void
63bpobj_decr_empty(objset_t *os, dmu_tx_t *tx)
64{
65	dsl_pool_t *dp = dmu_objset_pool(os);
66
67	spa_feature_decr(dmu_objset_spa(os), SPA_FEATURE_EMPTY_BPOBJ, tx);
68	if (!spa_feature_is_active(dmu_objset_spa(os),
69	    SPA_FEATURE_EMPTY_BPOBJ)) {
70		VERIFY3U(0, ==, zap_remove(dp->dp_meta_objset,
71		    DMU_POOL_DIRECTORY_OBJECT,
72		    DMU_POOL_EMPTY_BPOBJ, tx));
73		VERIFY3U(0, ==, dmu_object_free(os, dp->dp_empty_bpobj, tx));
74		dp->dp_empty_bpobj = 0;
75	}
76}
77
78uint64_t
79bpobj_alloc(objset_t *os, int blocksize, dmu_tx_t *tx)
80{
81	int size;
82
83	if (spa_version(dmu_objset_spa(os)) < SPA_VERSION_BPOBJ_ACCOUNT)
84		size = BPOBJ_SIZE_V0;
85	else if (spa_version(dmu_objset_spa(os)) < SPA_VERSION_DEADLISTS)
86		size = BPOBJ_SIZE_V1;
87	else
88		size = sizeof (bpobj_phys_t);
89
90	return (dmu_object_alloc(os, DMU_OT_BPOBJ, blocksize,
91	    DMU_OT_BPOBJ_HDR, size, tx));
92}
93
94void
95bpobj_free(objset_t *os, uint64_t obj, dmu_tx_t *tx)
96{
97	int64_t i;
98	bpobj_t bpo;
99	dmu_object_info_t doi;
100	int epb;
101	dmu_buf_t *dbuf = NULL;
102
103	ASSERT(obj != dmu_objset_pool(os)->dp_empty_bpobj);
104	VERIFY3U(0, ==, bpobj_open(&bpo, os, obj));
105
106	mutex_enter(&bpo.bpo_lock);
107
108	if (!bpo.bpo_havesubobj || bpo.bpo_phys->bpo_subobjs == 0)
109		goto out;
110
111	VERIFY3U(0, ==, dmu_object_info(os, bpo.bpo_phys->bpo_subobjs, &doi));
112	epb = doi.doi_data_block_size / sizeof (uint64_t);
113
114	for (i = bpo.bpo_phys->bpo_num_subobjs - 1; i >= 0; i--) {
115		uint64_t *objarray;
116		uint64_t offset, blkoff;
117
118		offset = i * sizeof (uint64_t);
119		blkoff = P2PHASE(i, epb);
120
121		if (dbuf == NULL || dbuf->db_offset > offset) {
122			if (dbuf)
123				dmu_buf_rele(dbuf, FTAG);
124			VERIFY3U(0, ==, dmu_buf_hold(os,
125			    bpo.bpo_phys->bpo_subobjs, offset, FTAG, &dbuf, 0));
126		}
127
128		ASSERT3U(offset, >=, dbuf->db_offset);
129		ASSERT3U(offset, <, dbuf->db_offset + dbuf->db_size);
130
131		objarray = dbuf->db_data;
132		bpobj_free(os, objarray[blkoff], tx);
133	}
134	if (dbuf) {
135		dmu_buf_rele(dbuf, FTAG);
136		dbuf = NULL;
137	}
138	VERIFY3U(0, ==, dmu_object_free(os, bpo.bpo_phys->bpo_subobjs, tx));
139
140out:
141	mutex_exit(&bpo.bpo_lock);
142	bpobj_close(&bpo);
143
144	VERIFY3U(0, ==, dmu_object_free(os, obj, tx));
145}
146
147int
148bpobj_open(bpobj_t *bpo, objset_t *os, uint64_t object)
149{
150	dmu_object_info_t doi;
151	int err;
152
153	err = dmu_object_info(os, object, &doi);
154	if (err)
155		return (err);
156
157	bzero(bpo, sizeof (*bpo));
158	mutex_init(&bpo->bpo_lock, NULL, MUTEX_DEFAULT, NULL);
159
160	ASSERT(bpo->bpo_dbuf == NULL);
161	ASSERT(bpo->bpo_phys == NULL);
162	ASSERT(object != 0);
163	ASSERT3U(doi.doi_type, ==, DMU_OT_BPOBJ);
164	ASSERT3U(doi.doi_bonus_type, ==, DMU_OT_BPOBJ_HDR);
165
166	err = dmu_bonus_hold(os, object, bpo, &bpo->bpo_dbuf);
167	if (err)
168		return (err);
169
170	bpo->bpo_os = os;
171	bpo->bpo_object = object;
172	bpo->bpo_epb = doi.doi_data_block_size >> SPA_BLKPTRSHIFT;
173	bpo->bpo_havecomp = (doi.doi_bonus_size > BPOBJ_SIZE_V0);
174	bpo->bpo_havesubobj = (doi.doi_bonus_size > BPOBJ_SIZE_V1);
175	bpo->bpo_phys = bpo->bpo_dbuf->db_data;
176	return (0);
177}
178
179boolean_t
180bpobj_is_open(const bpobj_t *bpo)
181{
182	return (bpo->bpo_object != 0);
183}
184
185void
186bpobj_close(bpobj_t *bpo)
187{
188	/* Lame workaround for closing a bpobj that was never opened. */
189	if (bpo->bpo_object == 0)
190		return;
191
192	dmu_buf_rele(bpo->bpo_dbuf, bpo);
193	if (bpo->bpo_cached_dbuf != NULL)
194		dmu_buf_rele(bpo->bpo_cached_dbuf, bpo);
195	bpo->bpo_dbuf = NULL;
196	bpo->bpo_phys = NULL;
197	bpo->bpo_cached_dbuf = NULL;
198	bpo->bpo_object = 0;
199
200	mutex_destroy(&bpo->bpo_lock);
201}
202
203boolean_t
204bpobj_is_empty(bpobj_t *bpo)
205{
206	return (bpo->bpo_phys->bpo_num_blkptrs == 0 &&
207	    (!bpo->bpo_havesubobj || bpo->bpo_phys->bpo_num_subobjs == 0));
208}
209
210static int
211bpobj_iterate_impl(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx,
212    boolean_t free)
213{
214	dmu_object_info_t doi;
215	int epb;
216	int64_t i;
217	int err = 0;
218	dmu_buf_t *dbuf = NULL;
219
220	ASSERT(bpobj_is_open(bpo));
221	mutex_enter(&bpo->bpo_lock);
222
223	if (free)
224		dmu_buf_will_dirty(bpo->bpo_dbuf, tx);
225
226	for (i = bpo->bpo_phys->bpo_num_blkptrs - 1; i >= 0; i--) {
227		blkptr_t *bparray;
228		blkptr_t *bp;
229		uint64_t offset, blkoff;
230
231		offset = i * sizeof (blkptr_t);
232		blkoff = P2PHASE(i, bpo->bpo_epb);
233
234		if (dbuf == NULL || dbuf->db_offset > offset) {
235			if (dbuf)
236				dmu_buf_rele(dbuf, FTAG);
237			err = dmu_buf_hold(bpo->bpo_os, bpo->bpo_object, offset,
238			    FTAG, &dbuf, 0);
239			if (err)
240				break;
241		}
242
243		ASSERT3U(offset, >=, dbuf->db_offset);
244		ASSERT3U(offset, <, dbuf->db_offset + dbuf->db_size);
245
246		bparray = dbuf->db_data;
247		bp = &bparray[blkoff];
248		err = func(arg, bp, tx);
249		if (err)
250			break;
251		if (free) {
252			bpo->bpo_phys->bpo_bytes -=
253			    bp_get_dsize_sync(dmu_objset_spa(bpo->bpo_os), bp);
254			ASSERT3S(bpo->bpo_phys->bpo_bytes, >=, 0);
255			if (bpo->bpo_havecomp) {
256				bpo->bpo_phys->bpo_comp -= BP_GET_PSIZE(bp);
257				bpo->bpo_phys->bpo_uncomp -= BP_GET_UCSIZE(bp);
258			}
259			bpo->bpo_phys->bpo_num_blkptrs--;
260			ASSERT3S(bpo->bpo_phys->bpo_num_blkptrs, >=, 0);
261		}
262	}
263	if (dbuf) {
264		dmu_buf_rele(dbuf, FTAG);
265		dbuf = NULL;
266	}
267	if (free) {
268		VERIFY3U(0, ==, dmu_free_range(bpo->bpo_os, bpo->bpo_object,
269		    (i + 1) * sizeof (blkptr_t), -1ULL, tx));
270	}
271	if (err || !bpo->bpo_havesubobj || bpo->bpo_phys->bpo_subobjs == 0)
272		goto out;
273
274	ASSERT(bpo->bpo_havecomp);
275	err = dmu_object_info(bpo->bpo_os, bpo->bpo_phys->bpo_subobjs, &doi);
276	if (err) {
277		mutex_exit(&bpo->bpo_lock);
278		return (err);
279	}
280	ASSERT3U(doi.doi_type, ==, DMU_OT_BPOBJ_SUBOBJ);
281	epb = doi.doi_data_block_size / sizeof (uint64_t);
282
283	for (i = bpo->bpo_phys->bpo_num_subobjs - 1; i >= 0; i--) {
284		uint64_t *objarray;
285		uint64_t offset, blkoff;
286		bpobj_t sublist;
287		uint64_t used_before, comp_before, uncomp_before;
288		uint64_t used_after, comp_after, uncomp_after;
289
290		offset = i * sizeof (uint64_t);
291		blkoff = P2PHASE(i, epb);
292
293		if (dbuf == NULL || dbuf->db_offset > offset) {
294			if (dbuf)
295				dmu_buf_rele(dbuf, FTAG);
296			err = dmu_buf_hold(bpo->bpo_os,
297			    bpo->bpo_phys->bpo_subobjs, offset, FTAG, &dbuf, 0);
298			if (err)
299				break;
300		}
301
302		ASSERT3U(offset, >=, dbuf->db_offset);
303		ASSERT3U(offset, <, dbuf->db_offset + dbuf->db_size);
304
305		objarray = dbuf->db_data;
306		err = bpobj_open(&sublist, bpo->bpo_os, objarray[blkoff]);
307		if (err)
308			break;
309		if (free) {
310			err = bpobj_space(&sublist,
311			    &used_before, &comp_before, &uncomp_before);
312			if (err != 0) {
313				bpobj_close(&sublist);
314				break;
315			}
316		}
317		err = bpobj_iterate_impl(&sublist, func, arg, tx, free);
318		if (free) {
319			VERIFY3U(0, ==, bpobj_space(&sublist,
320			    &used_after, &comp_after, &uncomp_after));
321			bpo->bpo_phys->bpo_bytes -= used_before - used_after;
322			ASSERT3S(bpo->bpo_phys->bpo_bytes, >=, 0);
323			bpo->bpo_phys->bpo_comp -= comp_before - comp_after;
324			bpo->bpo_phys->bpo_uncomp -=
325			    uncomp_before - uncomp_after;
326		}
327
328		bpobj_close(&sublist);
329		if (err)
330			break;
331		if (free) {
332			err = dmu_object_free(bpo->bpo_os,
333			    objarray[blkoff], tx);
334			if (err)
335				break;
336			bpo->bpo_phys->bpo_num_subobjs--;
337			ASSERT3S(bpo->bpo_phys->bpo_num_subobjs, >=, 0);
338		}
339	}
340	if (dbuf) {
341		dmu_buf_rele(dbuf, FTAG);
342		dbuf = NULL;
343	}
344	if (free) {
345		VERIFY3U(0, ==, dmu_free_range(bpo->bpo_os,
346		    bpo->bpo_phys->bpo_subobjs,
347		    (i + 1) * sizeof (uint64_t), -1ULL, tx));
348	}
349
350out:
351	/* If there are no entries, there should be no bytes. */
352	if (bpobj_is_empty(bpo)) {
353		ASSERT0(bpo->bpo_phys->bpo_bytes);
354		ASSERT0(bpo->bpo_phys->bpo_comp);
355		ASSERT0(bpo->bpo_phys->bpo_uncomp);
356	}
357
358	mutex_exit(&bpo->bpo_lock);
359	return (err);
360}
361
362/*
363 * Iterate and remove the entries.  If func returns nonzero, iteration
364 * will stop and that entry will not be removed.
365 */
366int
367bpobj_iterate(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx)
368{
369	return (bpobj_iterate_impl(bpo, func, arg, tx, B_TRUE));
370}
371
372/*
373 * Iterate the entries.  If func returns nonzero, iteration will stop.
374 */
375int
376bpobj_iterate_nofree(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx)
377{
378	return (bpobj_iterate_impl(bpo, func, arg, tx, B_FALSE));
379}
380
381void
382bpobj_enqueue_subobj(bpobj_t *bpo, uint64_t subobj, dmu_tx_t *tx)
383{
384	bpobj_t subbpo;
385	uint64_t used, comp, uncomp, subsubobjs;
386
387	ASSERT(bpobj_is_open(bpo));
388	ASSERT(subobj != 0);
389	ASSERT(bpo->bpo_havesubobj);
390	ASSERT(bpo->bpo_havecomp);
391	ASSERT(bpo->bpo_object != dmu_objset_pool(bpo->bpo_os)->dp_empty_bpobj);
392
393	if (subobj == dmu_objset_pool(bpo->bpo_os)->dp_empty_bpobj) {
394		bpobj_decr_empty(bpo->bpo_os, tx);
395		return;
396	}
397
398	VERIFY3U(0, ==, bpobj_open(&subbpo, bpo->bpo_os, subobj));
399	VERIFY3U(0, ==, bpobj_space(&subbpo, &used, &comp, &uncomp));
400
401	if (bpobj_is_empty(&subbpo)) {
402		/* No point in having an empty subobj. */
403		bpobj_close(&subbpo);
404		bpobj_free(bpo->bpo_os, subobj, tx);
405		return;
406	}
407
408	mutex_enter(&bpo->bpo_lock);
409	dmu_buf_will_dirty(bpo->bpo_dbuf, tx);
410	if (bpo->bpo_phys->bpo_subobjs == 0) {
411		bpo->bpo_phys->bpo_subobjs = dmu_object_alloc(bpo->bpo_os,
412		    DMU_OT_BPOBJ_SUBOBJ, SPA_OLD_MAXBLOCKSIZE,
413		    DMU_OT_NONE, 0, tx);
414	}
415
416	dmu_object_info_t doi;
417	ASSERT0(dmu_object_info(bpo->bpo_os, bpo->bpo_phys->bpo_subobjs, &doi));
418	ASSERT3U(doi.doi_type, ==, DMU_OT_BPOBJ_SUBOBJ);
419
420	dmu_write(bpo->bpo_os, bpo->bpo_phys->bpo_subobjs,
421	    bpo->bpo_phys->bpo_num_subobjs * sizeof (subobj),
422	    sizeof (subobj), &subobj, tx);
423	bpo->bpo_phys->bpo_num_subobjs++;
424
425	/*
426	 * If subobj has only one block of subobjs, then move subobj's
427	 * subobjs to bpo's subobj list directly.  This reduces
428	 * recursion in bpobj_iterate due to nested subobjs.
429	 */
430	subsubobjs = subbpo.bpo_phys->bpo_subobjs;
431	if (subsubobjs != 0) {
432		dmu_object_info_t doi;
433
434		VERIFY3U(0, ==, dmu_object_info(bpo->bpo_os, subsubobjs, &doi));
435		if (doi.doi_max_offset == doi.doi_data_block_size) {
436			dmu_buf_t *subdb;
437			uint64_t numsubsub = subbpo.bpo_phys->bpo_num_subobjs;
438
439			VERIFY3U(0, ==, dmu_buf_hold(bpo->bpo_os, subsubobjs,
440			    0, FTAG, &subdb, 0));
441			/*
442			 * Make sure that we are not asking dmu_write()
443			 * to write more data than we have in our buffer.
444			 */
445			VERIFY3U(subdb->db_size, >=,
446			    numsubsub * sizeof (subobj));
447			dmu_write(bpo->bpo_os, bpo->bpo_phys->bpo_subobjs,
448			    bpo->bpo_phys->bpo_num_subobjs * sizeof (subobj),
449			    numsubsub * sizeof (subobj), subdb->db_data, tx);
450			dmu_buf_rele(subdb, FTAG);
451			bpo->bpo_phys->bpo_num_subobjs += numsubsub;
452
453			dmu_buf_will_dirty(subbpo.bpo_dbuf, tx);
454			subbpo.bpo_phys->bpo_subobjs = 0;
455			VERIFY3U(0, ==, dmu_object_free(bpo->bpo_os,
456			    subsubobjs, tx));
457		}
458	}
459	bpo->bpo_phys->bpo_bytes += used;
460	bpo->bpo_phys->bpo_comp += comp;
461	bpo->bpo_phys->bpo_uncomp += uncomp;
462	mutex_exit(&bpo->bpo_lock);
463
464	bpobj_close(&subbpo);
465}
466
467void
468bpobj_enqueue(bpobj_t *bpo, const blkptr_t *bp, dmu_tx_t *tx)
469{
470	blkptr_t stored_bp = *bp;
471	uint64_t offset;
472	int blkoff;
473	blkptr_t *bparray;
474
475	ASSERT(bpobj_is_open(bpo));
476	ASSERT(!BP_IS_HOLE(bp));
477	ASSERT(bpo->bpo_object != dmu_objset_pool(bpo->bpo_os)->dp_empty_bpobj);
478
479	if (BP_IS_EMBEDDED(bp)) {
480		/*
481		 * The bpobj will compress better without the payload.
482		 *
483		 * Note that we store EMBEDDED bp's because they have an
484		 * uncompressed size, which must be accounted for.  An
485		 * alternative would be to add their size to bpo_uncomp
486		 * without storing the bp, but that would create additional
487		 * complications: bpo_uncomp would be inconsistent with the
488		 * set of BP's stored, and bpobj_iterate() wouldn't visit
489		 * all the space accounted for in the bpobj.
490		 */
491		bzero(&stored_bp, sizeof (stored_bp));
492		stored_bp.blk_prop = bp->blk_prop;
493		stored_bp.blk_birth = bp->blk_birth;
494	} else if (!BP_GET_DEDUP(bp)) {
495		/* The bpobj will compress better without the checksum */
496		bzero(&stored_bp.blk_cksum, sizeof (stored_bp.blk_cksum));
497	}
498
499	/* We never need the fill count. */
500	stored_bp.blk_fill = 0;
501
502	mutex_enter(&bpo->bpo_lock);
503
504	offset = bpo->bpo_phys->bpo_num_blkptrs * sizeof (stored_bp);
505	blkoff = P2PHASE(bpo->bpo_phys->bpo_num_blkptrs, bpo->bpo_epb);
506
507	if (bpo->bpo_cached_dbuf == NULL ||
508	    offset < bpo->bpo_cached_dbuf->db_offset ||
509	    offset >= bpo->bpo_cached_dbuf->db_offset +
510	    bpo->bpo_cached_dbuf->db_size) {
511		if (bpo->bpo_cached_dbuf)
512			dmu_buf_rele(bpo->bpo_cached_dbuf, bpo);
513		VERIFY3U(0, ==, dmu_buf_hold(bpo->bpo_os, bpo->bpo_object,
514		    offset, bpo, &bpo->bpo_cached_dbuf, 0));
515	}
516
517	dmu_buf_will_dirty(bpo->bpo_cached_dbuf, tx);
518	bparray = bpo->bpo_cached_dbuf->db_data;
519	bparray[blkoff] = stored_bp;
520
521	dmu_buf_will_dirty(bpo->bpo_dbuf, tx);
522	bpo->bpo_phys->bpo_num_blkptrs++;
523	bpo->bpo_phys->bpo_bytes +=
524	    bp_get_dsize_sync(dmu_objset_spa(bpo->bpo_os), bp);
525	if (bpo->bpo_havecomp) {
526		bpo->bpo_phys->bpo_comp += BP_GET_PSIZE(bp);
527		bpo->bpo_phys->bpo_uncomp += BP_GET_UCSIZE(bp);
528	}
529	mutex_exit(&bpo->bpo_lock);
530}
531
532struct space_range_arg {
533	spa_t *spa;
534	uint64_t mintxg;
535	uint64_t maxtxg;
536	uint64_t used;
537	uint64_t comp;
538	uint64_t uncomp;
539};
540
541/* ARGSUSED */
542static int
543space_range_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
544{
545	struct space_range_arg *sra = arg;
546
547	if (bp->blk_birth > sra->mintxg && bp->blk_birth <= sra->maxtxg) {
548		if (dsl_pool_sync_context(spa_get_dsl(sra->spa)))
549			sra->used += bp_get_dsize_sync(sra->spa, bp);
550		else
551			sra->used += bp_get_dsize(sra->spa, bp);
552		sra->comp += BP_GET_PSIZE(bp);
553		sra->uncomp += BP_GET_UCSIZE(bp);
554	}
555	return (0);
556}
557
558int
559bpobj_space(bpobj_t *bpo, uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
560{
561	ASSERT(bpobj_is_open(bpo));
562	mutex_enter(&bpo->bpo_lock);
563
564	*usedp = bpo->bpo_phys->bpo_bytes;
565	if (bpo->bpo_havecomp) {
566		*compp = bpo->bpo_phys->bpo_comp;
567		*uncompp = bpo->bpo_phys->bpo_uncomp;
568		mutex_exit(&bpo->bpo_lock);
569		return (0);
570	} else {
571		mutex_exit(&bpo->bpo_lock);
572		return (bpobj_space_range(bpo, 0, UINT64_MAX,
573		    usedp, compp, uncompp));
574	}
575}
576
577/*
578 * Return the amount of space in the bpobj which is:
579 * mintxg < blk_birth <= maxtxg
580 */
581int
582bpobj_space_range(bpobj_t *bpo, uint64_t mintxg, uint64_t maxtxg,
583    uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
584{
585	struct space_range_arg sra = { 0 };
586	int err;
587
588	ASSERT(bpobj_is_open(bpo));
589
590	/*
591	 * As an optimization, if they want the whole txg range, just
592	 * get bpo_bytes rather than iterating over the bps.
593	 */
594	if (mintxg < TXG_INITIAL && maxtxg == UINT64_MAX && bpo->bpo_havecomp)
595		return (bpobj_space(bpo, usedp, compp, uncompp));
596
597	sra.spa = dmu_objset_spa(bpo->bpo_os);
598	sra.mintxg = mintxg;
599	sra.maxtxg = maxtxg;
600
601	err = bpobj_iterate_nofree(bpo, space_range_cb, &sra, NULL);
602	*usedp = sra.used;
603	*compp = sra.comp;
604	*uncompp = sra.uncomp;
605	return (err);
606}
607