bpobj.c revision 263390 
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) 2013 by Delphix. All rights reserved.
24 */
25
26#include <sys/bpobj.h>
27#include <sys/zfs_context.h>
28#include <sys/refcount.h>
29#include <sys/dsl_pool.h>
30#include <sys/zfeature.h>
31#include <sys/zap.h>
32
33/*
34 * Return an empty bpobj, preferably the empty dummy one (dp_empty_bpobj).
35 */
36uint64_t
37bpobj_alloc_empty(objset_t *os, int blocksize, dmu_tx_t *tx)
38{
39	spa_t *spa = dmu_objset_spa(os);
40	dsl_pool_t *dp = dmu_objset_pool(os);
41
42	if (spa_feature_is_enabled(spa, SPA_FEATURE_EMPTY_BPOBJ)) {
43		if (!spa_feature_is_active(spa, SPA_FEATURE_EMPTY_BPOBJ)) {
44			ASSERT0(dp->dp_empty_bpobj);
45			dp->dp_empty_bpobj =
46			    bpobj_alloc(os, SPA_MAXBLOCKSIZE, tx);
47			VERIFY(zap_add(os,
48			    DMU_POOL_DIRECTORY_OBJECT,
49			    DMU_POOL_EMPTY_BPOBJ, sizeof (uint64_t), 1,
50			    &dp->dp_empty_bpobj, tx) == 0);
51		}
52		spa_feature_incr(spa, SPA_FEATURE_EMPTY_BPOBJ, tx);
53		ASSERT(dp->dp_empty_bpobj != 0);
54		return (dp->dp_empty_bpobj);
55	} else {
56		return (bpobj_alloc(os, blocksize, tx));
57	}
58}
59
60void
61bpobj_decr_empty(objset_t *os, dmu_tx_t *tx)
62{
63	dsl_pool_t *dp = dmu_objset_pool(os);
64
65	spa_feature_decr(dmu_objset_spa(os), SPA_FEATURE_EMPTY_BPOBJ, tx);
66	if (!spa_feature_is_active(dmu_objset_spa(os),
67	    SPA_FEATURE_EMPTY_BPOBJ)) {
68		VERIFY3U(0, ==, zap_remove(dp->dp_meta_objset,
69		    DMU_POOL_DIRECTORY_OBJECT,
70		    DMU_POOL_EMPTY_BPOBJ, tx));
71		VERIFY3U(0, ==, dmu_object_free(os, dp->dp_empty_bpobj, tx));
72		dp->dp_empty_bpobj = 0;
73	}
74}
75
76uint64_t
77bpobj_alloc(objset_t *os, int blocksize, dmu_tx_t *tx)
78{
79	int size;
80
81	if (spa_version(dmu_objset_spa(os)) < SPA_VERSION_BPOBJ_ACCOUNT)
82		size = BPOBJ_SIZE_V0;
83	else if (spa_version(dmu_objset_spa(os)) < SPA_VERSION_DEADLISTS)
84		size = BPOBJ_SIZE_V1;
85	else
86		size = sizeof (bpobj_phys_t);
87
88	return (dmu_object_alloc(os, DMU_OT_BPOBJ, blocksize,
89	    DMU_OT_BPOBJ_HDR, size, tx));
90}
91
92void
93bpobj_free(objset_t *os, uint64_t obj, dmu_tx_t *tx)
94{
95	int64_t i;
96	bpobj_t bpo;
97	dmu_object_info_t doi;
98	int epb;
99	dmu_buf_t *dbuf = NULL;
100
101	ASSERT(obj != dmu_objset_pool(os)->dp_empty_bpobj);
102	VERIFY3U(0, ==, bpobj_open(&bpo, os, obj));
103
104	mutex_enter(&bpo.bpo_lock);
105
106	if (!bpo.bpo_havesubobj || bpo.bpo_phys->bpo_subobjs == 0)
107		goto out;
108
109	VERIFY3U(0, ==, dmu_object_info(os, bpo.bpo_phys->bpo_subobjs, &doi));
110	epb = doi.doi_data_block_size / sizeof (uint64_t);
111
112	for (i = bpo.bpo_phys->bpo_num_subobjs - 1; i >= 0; i--) {
113		uint64_t *objarray;
114		uint64_t offset, blkoff;
115
116		offset = i * sizeof (uint64_t);
117		blkoff = P2PHASE(i, epb);
118
119		if (dbuf == NULL || dbuf->db_offset > offset) {
120			if (dbuf)
121				dmu_buf_rele(dbuf, FTAG);
122			VERIFY3U(0, ==, dmu_buf_hold(os,
123			    bpo.bpo_phys->bpo_subobjs, offset, FTAG, &dbuf, 0));
124		}
125
126		ASSERT3U(offset, >=, dbuf->db_offset);
127		ASSERT3U(offset, <, dbuf->db_offset + dbuf->db_size);
128
129		objarray = dbuf->db_data;
130		bpobj_free(os, objarray[blkoff], tx);
131	}
132	if (dbuf) {
133		dmu_buf_rele(dbuf, FTAG);
134		dbuf = NULL;
135	}
136	VERIFY3U(0, ==, dmu_object_free(os, bpo.bpo_phys->bpo_subobjs, tx));
137
138out:
139	mutex_exit(&bpo.bpo_lock);
140	bpobj_close(&bpo);
141
142	VERIFY3U(0, ==, dmu_object_free(os, obj, tx));
143}
144
145int
146bpobj_open(bpobj_t *bpo, objset_t *os, uint64_t object)
147{
148	dmu_object_info_t doi;
149	int err;
150
151	err = dmu_object_info(os, object, &doi);
152	if (err)
153		return (err);
154
155	bzero(bpo, sizeof (*bpo));
156	mutex_init(&bpo->bpo_lock, NULL, MUTEX_DEFAULT, NULL);
157
158	ASSERT(bpo->bpo_dbuf == NULL);
159	ASSERT(bpo->bpo_phys == NULL);
160	ASSERT(object != 0);
161	ASSERT3U(doi.doi_type, ==, DMU_OT_BPOBJ);
162	ASSERT3U(doi.doi_bonus_type, ==, DMU_OT_BPOBJ_HDR);
163
164	err = dmu_bonus_hold(os, object, bpo, &bpo->bpo_dbuf);
165	if (err)
166		return (err);
167
168	bpo->bpo_os = os;
169	bpo->bpo_object = object;
170	bpo->bpo_epb = doi.doi_data_block_size >> SPA_BLKPTRSHIFT;
171	bpo->bpo_havecomp = (doi.doi_bonus_size > BPOBJ_SIZE_V0);
172	bpo->bpo_havesubobj = (doi.doi_bonus_size > BPOBJ_SIZE_V1);
173	bpo->bpo_phys = bpo->bpo_dbuf->db_data;
174	return (0);
175}
176
177void
178bpobj_close(bpobj_t *bpo)
179{
180	/* Lame workaround for closing a bpobj that was never opened. */
181	if (bpo->bpo_object == 0)
182		return;
183
184	dmu_buf_rele(bpo->bpo_dbuf, bpo);
185	if (bpo->bpo_cached_dbuf != NULL)
186		dmu_buf_rele(bpo->bpo_cached_dbuf, bpo);
187	bpo->bpo_dbuf = NULL;
188	bpo->bpo_phys = NULL;
189	bpo->bpo_cached_dbuf = NULL;
190	bpo->bpo_object = 0;
191
192	mutex_destroy(&bpo->bpo_lock);
193}
194
195static int
196bpobj_iterate_impl(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx,
197    boolean_t free)
198{
199	dmu_object_info_t doi;
200	int epb;
201	int64_t i;
202	int err = 0;
203	dmu_buf_t *dbuf = NULL;
204
205	mutex_enter(&bpo->bpo_lock);
206
207	if (free)
208		dmu_buf_will_dirty(bpo->bpo_dbuf, tx);
209
210	for (i = bpo->bpo_phys->bpo_num_blkptrs - 1; i >= 0; i--) {
211		blkptr_t *bparray;
212		blkptr_t *bp;
213		uint64_t offset, blkoff;
214
215		offset = i * sizeof (blkptr_t);
216		blkoff = P2PHASE(i, bpo->bpo_epb);
217
218		if (dbuf == NULL || dbuf->db_offset > offset) {
219			if (dbuf)
220				dmu_buf_rele(dbuf, FTAG);
221			err = dmu_buf_hold(bpo->bpo_os, bpo->bpo_object, offset,
222			    FTAG, &dbuf, 0);
223			if (err)
224				break;
225		}
226
227		ASSERT3U(offset, >=, dbuf->db_offset);
228		ASSERT3U(offset, <, dbuf->db_offset + dbuf->db_size);
229
230		bparray = dbuf->db_data;
231		bp = &bparray[blkoff];
232		err = func(arg, bp, tx);
233		if (err)
234			break;
235		if (free) {
236			bpo->bpo_phys->bpo_bytes -=
237			    bp_get_dsize_sync(dmu_objset_spa(bpo->bpo_os), bp);
238			ASSERT3S(bpo->bpo_phys->bpo_bytes, >=, 0);
239			if (bpo->bpo_havecomp) {
240				bpo->bpo_phys->bpo_comp -= BP_GET_PSIZE(bp);
241				bpo->bpo_phys->bpo_uncomp -= BP_GET_UCSIZE(bp);
242			}
243			bpo->bpo_phys->bpo_num_blkptrs--;
244			ASSERT3S(bpo->bpo_phys->bpo_num_blkptrs, >=, 0);
245		}
246	}
247	if (dbuf) {
248		dmu_buf_rele(dbuf, FTAG);
249		dbuf = NULL;
250	}
251	if (free) {
252		i++;
253		VERIFY3U(0, ==, dmu_free_range(bpo->bpo_os, bpo->bpo_object,
254		    i * sizeof (blkptr_t), -1ULL, tx));
255	}
256	if (err || !bpo->bpo_havesubobj || bpo->bpo_phys->bpo_subobjs == 0)
257		goto out;
258
259	ASSERT(bpo->bpo_havecomp);
260	err = dmu_object_info(bpo->bpo_os, bpo->bpo_phys->bpo_subobjs, &doi);
261	if (err) {
262		mutex_exit(&bpo->bpo_lock);
263		return (err);
264	}
265	ASSERT3U(doi.doi_type, ==, DMU_OT_BPOBJ_SUBOBJ);
266	epb = doi.doi_data_block_size / sizeof (uint64_t);
267
268	for (i = bpo->bpo_phys->bpo_num_subobjs - 1; i >= 0; i--) {
269		uint64_t *objarray;
270		uint64_t offset, blkoff;
271		bpobj_t sublist;
272		uint64_t used_before, comp_before, uncomp_before;
273		uint64_t used_after, comp_after, uncomp_after;
274
275		offset = i * sizeof (uint64_t);
276		blkoff = P2PHASE(i, epb);
277
278		if (dbuf == NULL || dbuf->db_offset > offset) {
279			if (dbuf)
280				dmu_buf_rele(dbuf, FTAG);
281			err = dmu_buf_hold(bpo->bpo_os,
282			    bpo->bpo_phys->bpo_subobjs, offset, FTAG, &dbuf, 0);
283			if (err)
284				break;
285		}
286
287		ASSERT3U(offset, >=, dbuf->db_offset);
288		ASSERT3U(offset, <, dbuf->db_offset + dbuf->db_size);
289
290		objarray = dbuf->db_data;
291		err = bpobj_open(&sublist, bpo->bpo_os, objarray[blkoff]);
292		if (err)
293			break;
294		if (free) {
295			err = bpobj_space(&sublist,
296			    &used_before, &comp_before, &uncomp_before);
297			if (err)
298				break;
299		}
300		err = bpobj_iterate_impl(&sublist, func, arg, tx, free);
301		if (free) {
302			VERIFY3U(0, ==, bpobj_space(&sublist,
303			    &used_after, &comp_after, &uncomp_after));
304			bpo->bpo_phys->bpo_bytes -= used_before - used_after;
305			ASSERT3S(bpo->bpo_phys->bpo_bytes, >=, 0);
306			bpo->bpo_phys->bpo_comp -= comp_before - comp_after;
307			bpo->bpo_phys->bpo_uncomp -=
308			    uncomp_before - uncomp_after;
309		}
310
311		bpobj_close(&sublist);
312		if (err)
313			break;
314		if (free) {
315			err = dmu_object_free(bpo->bpo_os,
316			    objarray[blkoff], tx);
317			if (err)
318				break;
319			bpo->bpo_phys->bpo_num_subobjs--;
320			ASSERT3S(bpo->bpo_phys->bpo_num_subobjs, >=, 0);
321		}
322	}
323	if (dbuf) {
324		dmu_buf_rele(dbuf, FTAG);
325		dbuf = NULL;
326	}
327	if (free) {
328		VERIFY3U(0, ==, dmu_free_range(bpo->bpo_os,
329		    bpo->bpo_phys->bpo_subobjs,
330		    (i + 1) * sizeof (uint64_t), -1ULL, tx));
331	}
332
333out:
334	/* If there are no entries, there should be no bytes. */
335	ASSERT(bpo->bpo_phys->bpo_num_blkptrs > 0 ||
336	    (bpo->bpo_havesubobj && bpo->bpo_phys->bpo_num_subobjs > 0) ||
337	    bpo->bpo_phys->bpo_bytes == 0);
338
339	mutex_exit(&bpo->bpo_lock);
340	return (err);
341}
342
343/*
344 * Iterate and remove the entries.  If func returns nonzero, iteration
345 * will stop and that entry will not be removed.
346 */
347int
348bpobj_iterate(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx)
349{
350	return (bpobj_iterate_impl(bpo, func, arg, tx, B_TRUE));
351}
352
353/*
354 * Iterate the entries.  If func returns nonzero, iteration will stop.
355 */
356int
357bpobj_iterate_nofree(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx)
358{
359	return (bpobj_iterate_impl(bpo, func, arg, tx, B_FALSE));
360}
361
362void
363bpobj_enqueue_subobj(bpobj_t *bpo, uint64_t subobj, dmu_tx_t *tx)
364{
365	bpobj_t subbpo;
366	uint64_t used, comp, uncomp, subsubobjs;
367
368	ASSERT(bpo->bpo_havesubobj);
369	ASSERT(bpo->bpo_havecomp);
370	ASSERT(bpo->bpo_object != dmu_objset_pool(bpo->bpo_os)->dp_empty_bpobj);
371
372	if (subobj == dmu_objset_pool(bpo->bpo_os)->dp_empty_bpobj) {
373		bpobj_decr_empty(bpo->bpo_os, tx);
374		return;
375	}
376
377	VERIFY3U(0, ==, bpobj_open(&subbpo, bpo->bpo_os, subobj));
378	VERIFY3U(0, ==, bpobj_space(&subbpo, &used, &comp, &uncomp));
379
380	if (used == 0) {
381		/* No point in having an empty subobj. */
382		bpobj_close(&subbpo);
383		bpobj_free(bpo->bpo_os, subobj, tx);
384		return;
385	}
386
387	dmu_buf_will_dirty(bpo->bpo_dbuf, tx);
388	if (bpo->bpo_phys->bpo_subobjs == 0) {
389		bpo->bpo_phys->bpo_subobjs = dmu_object_alloc(bpo->bpo_os,
390		    DMU_OT_BPOBJ_SUBOBJ, SPA_MAXBLOCKSIZE, DMU_OT_NONE, 0, tx);
391	}
392
393	dmu_object_info_t doi;
394	ASSERT0(dmu_object_info(bpo->bpo_os, bpo->bpo_phys->bpo_subobjs, &doi));
395	ASSERT3U(doi.doi_type, ==, DMU_OT_BPOBJ_SUBOBJ);
396
397	mutex_enter(&bpo->bpo_lock);
398	dmu_write(bpo->bpo_os, bpo->bpo_phys->bpo_subobjs,
399	    bpo->bpo_phys->bpo_num_subobjs * sizeof (subobj),
400	    sizeof (subobj), &subobj, tx);
401	bpo->bpo_phys->bpo_num_subobjs++;
402
403	/*
404	 * If subobj has only one block of subobjs, then move subobj's
405	 * subobjs to bpo's subobj list directly.  This reduces
406	 * recursion in bpobj_iterate due to nested subobjs.
407	 */
408	subsubobjs = subbpo.bpo_phys->bpo_subobjs;
409	if (subsubobjs != 0) {
410		dmu_object_info_t doi;
411
412		VERIFY3U(0, ==, dmu_object_info(bpo->bpo_os, subsubobjs, &doi));
413		if (doi.doi_max_offset == doi.doi_data_block_size) {
414			dmu_buf_t *subdb;
415			uint64_t numsubsub = subbpo.bpo_phys->bpo_num_subobjs;
416
417			VERIFY3U(0, ==, dmu_buf_hold(bpo->bpo_os, subsubobjs,
418			    0, FTAG, &subdb, 0));
419			/*
420			 * Make sure that we are not asking dmu_write()
421			 * to write more data than we have in our buffer.
422			 */
423			VERIFY3U(subdb->db_size, >=,
424			    numsubsub * sizeof (subobj));
425			dmu_write(bpo->bpo_os, bpo->bpo_phys->bpo_subobjs,
426			    bpo->bpo_phys->bpo_num_subobjs * sizeof (subobj),
427			    numsubsub * sizeof (subobj), subdb->db_data, tx);
428			dmu_buf_rele(subdb, FTAG);
429			bpo->bpo_phys->bpo_num_subobjs += numsubsub;
430
431			dmu_buf_will_dirty(subbpo.bpo_dbuf, tx);
432			subbpo.bpo_phys->bpo_subobjs = 0;
433			VERIFY3U(0, ==, dmu_object_free(bpo->bpo_os,
434			    subsubobjs, tx));
435		}
436	}
437	bpo->bpo_phys->bpo_bytes += used;
438	bpo->bpo_phys->bpo_comp += comp;
439	bpo->bpo_phys->bpo_uncomp += uncomp;
440	mutex_exit(&bpo->bpo_lock);
441
442	bpobj_close(&subbpo);
443}
444
445void
446bpobj_enqueue(bpobj_t *bpo, const blkptr_t *bp, dmu_tx_t *tx)
447{
448	blkptr_t stored_bp = *bp;
449	uint64_t offset;
450	int blkoff;
451	blkptr_t *bparray;
452
453	ASSERT(!BP_IS_HOLE(bp));
454	ASSERT(bpo->bpo_object != dmu_objset_pool(bpo->bpo_os)->dp_empty_bpobj);
455
456	/* We never need the fill count. */
457	stored_bp.blk_fill = 0;
458
459	/* The bpobj will compress better if we can leave off the checksum */
460	if (!BP_GET_DEDUP(bp))
461		bzero(&stored_bp.blk_cksum, sizeof (stored_bp.blk_cksum));
462
463	mutex_enter(&bpo->bpo_lock);
464
465	offset = bpo->bpo_phys->bpo_num_blkptrs * sizeof (stored_bp);
466	blkoff = P2PHASE(bpo->bpo_phys->bpo_num_blkptrs, bpo->bpo_epb);
467
468	if (bpo->bpo_cached_dbuf == NULL ||
469	    offset < bpo->bpo_cached_dbuf->db_offset ||
470	    offset >= bpo->bpo_cached_dbuf->db_offset +
471	    bpo->bpo_cached_dbuf->db_size) {
472		if (bpo->bpo_cached_dbuf)
473			dmu_buf_rele(bpo->bpo_cached_dbuf, bpo);
474		VERIFY3U(0, ==, dmu_buf_hold(bpo->bpo_os, bpo->bpo_object,
475		    offset, bpo, &bpo->bpo_cached_dbuf, 0));
476	}
477
478	dmu_buf_will_dirty(bpo->bpo_cached_dbuf, tx);
479	bparray = bpo->bpo_cached_dbuf->db_data;
480	bparray[blkoff] = stored_bp;
481
482	dmu_buf_will_dirty(bpo->bpo_dbuf, tx);
483	bpo->bpo_phys->bpo_num_blkptrs++;
484	bpo->bpo_phys->bpo_bytes +=
485	    bp_get_dsize_sync(dmu_objset_spa(bpo->bpo_os), bp);
486	if (bpo->bpo_havecomp) {
487		bpo->bpo_phys->bpo_comp += BP_GET_PSIZE(bp);
488		bpo->bpo_phys->bpo_uncomp += BP_GET_UCSIZE(bp);
489	}
490	mutex_exit(&bpo->bpo_lock);
491}
492
493struct space_range_arg {
494	spa_t *spa;
495	uint64_t mintxg;
496	uint64_t maxtxg;
497	uint64_t used;
498	uint64_t comp;
499	uint64_t uncomp;
500};
501
502/* ARGSUSED */
503static int
504space_range_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
505{
506	struct space_range_arg *sra = arg;
507
508	if (bp->blk_birth > sra->mintxg && bp->blk_birth <= sra->maxtxg) {
509		if (dsl_pool_sync_context(spa_get_dsl(sra->spa)))
510			sra->used += bp_get_dsize_sync(sra->spa, bp);
511		else
512			sra->used += bp_get_dsize(sra->spa, bp);
513		sra->comp += BP_GET_PSIZE(bp);
514		sra->uncomp += BP_GET_UCSIZE(bp);
515	}
516	return (0);
517}
518
519int
520bpobj_space(bpobj_t *bpo, uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
521{
522	mutex_enter(&bpo->bpo_lock);
523
524	*usedp = bpo->bpo_phys->bpo_bytes;
525	if (bpo->bpo_havecomp) {
526		*compp = bpo->bpo_phys->bpo_comp;
527		*uncompp = bpo->bpo_phys->bpo_uncomp;
528		mutex_exit(&bpo->bpo_lock);
529		return (0);
530	} else {
531		mutex_exit(&bpo->bpo_lock);
532		return (bpobj_space_range(bpo, 0, UINT64_MAX,
533		    usedp, compp, uncompp));
534	}
535}
536
537/*
538 * Return the amount of space in the bpobj which is:
539 * mintxg < blk_birth <= maxtxg
540 */
541int
542bpobj_space_range(bpobj_t *bpo, uint64_t mintxg, uint64_t maxtxg,
543    uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
544{
545	struct space_range_arg sra = { 0 };
546	int err;
547
548	/*
549	 * As an optimization, if they want the whole txg range, just
550	 * get bpo_bytes rather than iterating over the bps.
551	 */
552	if (mintxg < TXG_INITIAL && maxtxg == UINT64_MAX && bpo->bpo_havecomp)
553		return (bpobj_space(bpo, usedp, compp, uncompp));
554
555	sra.spa = dmu_objset_spa(bpo->bpo_os);
556	sra.mintxg = mintxg;
557	sra.maxtxg = maxtxg;
558
559	err = bpobj_iterate_nofree(bpo, space_range_cb, &sra, NULL);
560	*usedp = sra.used;
561	*compp = sra.comp;
562	*uncompp = sra.uncomp;
563	return (err);
564}
565