xref: /titanic_51/usr/src/uts/common/fs/zfs/dsl_deadlist.c (revision c3d26abc9ee97b4f60233556aadeb57e0bd30bb9)
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) 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2012 by Delphix. All rights reserved.
24  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
25  * Copyright (c) 2014 Integros [integros.com]
26  */
27 
28 #include <sys/dsl_dataset.h>
29 #include <sys/dmu.h>
30 #include <sys/refcount.h>
31 #include <sys/zap.h>
32 #include <sys/zfs_context.h>
33 #include <sys/dsl_pool.h>
34 
35 /*
36  * Deadlist concurrency:
37  *
38  * Deadlists can only be modified from the syncing thread.
39  *
40  * Except for dsl_deadlist_insert(), it can only be modified with the
41  * dp_config_rwlock held with RW_WRITER.
42  *
43  * The accessors (dsl_deadlist_space() and dsl_deadlist_space_range()) can
44  * be called concurrently, from open context, with the dl_config_rwlock held
45  * with RW_READER.
46  *
47  * Therefore, we only need to provide locking between dsl_deadlist_insert() and
48  * the accessors, protecting:
49  *     dl_phys->dl_used,comp,uncomp
50  *     and protecting the dl_tree from being loaded.
51  * The locking is provided by dl_lock.  Note that locking on the bpobj_t
52  * provides its own locking, and dl_oldfmt is immutable.
53  */
54 
55 static int
56 dsl_deadlist_compare(const void *arg1, const void *arg2)
57 {
58 	const dsl_deadlist_entry_t *dle1 = arg1;
59 	const dsl_deadlist_entry_t *dle2 = arg2;
60 
61 	if (dle1->dle_mintxg < dle2->dle_mintxg)
62 		return (-1);
63 	else if (dle1->dle_mintxg > dle2->dle_mintxg)
64 		return (+1);
65 	else
66 		return (0);
67 }
68 
69 static void
70 dsl_deadlist_load_tree(dsl_deadlist_t *dl)
71 {
72 	zap_cursor_t zc;
73 	zap_attribute_t za;
74 
75 	ASSERT(!dl->dl_oldfmt);
76 	if (dl->dl_havetree)
77 		return;
78 
79 	avl_create(&dl->dl_tree, dsl_deadlist_compare,
80 	    sizeof (dsl_deadlist_entry_t),
81 	    offsetof(dsl_deadlist_entry_t, dle_node));
82 	for (zap_cursor_init(&zc, dl->dl_os, dl->dl_object);
83 	    zap_cursor_retrieve(&zc, &za) == 0;
84 	    zap_cursor_advance(&zc)) {
85 		dsl_deadlist_entry_t *dle = kmem_alloc(sizeof (*dle), KM_SLEEP);
86 		dle->dle_mintxg = strtonum(za.za_name, NULL);
87 		VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os,
88 		    za.za_first_integer));
89 		avl_add(&dl->dl_tree, dle);
90 	}
91 	zap_cursor_fini(&zc);
92 	dl->dl_havetree = B_TRUE;
93 }
94 
95 void
96 dsl_deadlist_open(dsl_deadlist_t *dl, objset_t *os, uint64_t object)
97 {
98 	dmu_object_info_t doi;
99 
100 	mutex_init(&dl->dl_lock, NULL, MUTEX_DEFAULT, NULL);
101 	dl->dl_os = os;
102 	dl->dl_object = object;
103 	VERIFY3U(0, ==, dmu_bonus_hold(os, object, dl, &dl->dl_dbuf));
104 	dmu_object_info_from_db(dl->dl_dbuf, &doi);
105 	if (doi.doi_type == DMU_OT_BPOBJ) {
106 		dmu_buf_rele(dl->dl_dbuf, dl);
107 		dl->dl_dbuf = NULL;
108 		dl->dl_oldfmt = B_TRUE;
109 		VERIFY3U(0, ==, bpobj_open(&dl->dl_bpobj, os, object));
110 		return;
111 	}
112 
113 	dl->dl_oldfmt = B_FALSE;
114 	dl->dl_phys = dl->dl_dbuf->db_data;
115 	dl->dl_havetree = B_FALSE;
116 }
117 
118 void
119 dsl_deadlist_close(dsl_deadlist_t *dl)
120 {
121 	void *cookie = NULL;
122 	dsl_deadlist_entry_t *dle;
123 
124 	dl->dl_os = NULL;
125 
126 	if (dl->dl_oldfmt) {
127 		dl->dl_oldfmt = B_FALSE;
128 		bpobj_close(&dl->dl_bpobj);
129 		return;
130 	}
131 
132 	if (dl->dl_havetree) {
133 		while ((dle = avl_destroy_nodes(&dl->dl_tree, &cookie))
134 		    != NULL) {
135 			bpobj_close(&dle->dle_bpobj);
136 			kmem_free(dle, sizeof (*dle));
137 		}
138 		avl_destroy(&dl->dl_tree);
139 	}
140 	dmu_buf_rele(dl->dl_dbuf, dl);
141 	mutex_destroy(&dl->dl_lock);
142 	dl->dl_dbuf = NULL;
143 	dl->dl_phys = NULL;
144 }
145 
146 uint64_t
147 dsl_deadlist_alloc(objset_t *os, dmu_tx_t *tx)
148 {
149 	if (spa_version(dmu_objset_spa(os)) < SPA_VERSION_DEADLISTS)
150 		return (bpobj_alloc(os, SPA_OLD_MAXBLOCKSIZE, tx));
151 	return (zap_create(os, DMU_OT_DEADLIST, DMU_OT_DEADLIST_HDR,
152 	    sizeof (dsl_deadlist_phys_t), tx));
153 }
154 
155 void
156 dsl_deadlist_free(objset_t *os, uint64_t dlobj, dmu_tx_t *tx)
157 {
158 	dmu_object_info_t doi;
159 	zap_cursor_t zc;
160 	zap_attribute_t za;
161 
162 	VERIFY3U(0, ==, dmu_object_info(os, dlobj, &doi));
163 	if (doi.doi_type == DMU_OT_BPOBJ) {
164 		bpobj_free(os, dlobj, tx);
165 		return;
166 	}
167 
168 	for (zap_cursor_init(&zc, os, dlobj);
169 	    zap_cursor_retrieve(&zc, &za) == 0;
170 	    zap_cursor_advance(&zc)) {
171 		uint64_t obj = za.za_first_integer;
172 		if (obj == dmu_objset_pool(os)->dp_empty_bpobj)
173 			bpobj_decr_empty(os, tx);
174 		else
175 			bpobj_free(os, obj, tx);
176 	}
177 	zap_cursor_fini(&zc);
178 	VERIFY3U(0, ==, dmu_object_free(os, dlobj, tx));
179 }
180 
181 static void
182 dle_enqueue(dsl_deadlist_t *dl, dsl_deadlist_entry_t *dle,
183     const blkptr_t *bp, dmu_tx_t *tx)
184 {
185 	if (dle->dle_bpobj.bpo_object ==
186 	    dmu_objset_pool(dl->dl_os)->dp_empty_bpobj) {
187 		uint64_t obj = bpobj_alloc(dl->dl_os, SPA_OLD_MAXBLOCKSIZE, tx);
188 		bpobj_close(&dle->dle_bpobj);
189 		bpobj_decr_empty(dl->dl_os, tx);
190 		VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
191 		VERIFY3U(0, ==, zap_update_int_key(dl->dl_os, dl->dl_object,
192 		    dle->dle_mintxg, obj, tx));
193 	}
194 	bpobj_enqueue(&dle->dle_bpobj, bp, tx);
195 }
196 
197 static void
198 dle_enqueue_subobj(dsl_deadlist_t *dl, dsl_deadlist_entry_t *dle,
199     uint64_t obj, dmu_tx_t *tx)
200 {
201 	if (dle->dle_bpobj.bpo_object !=
202 	    dmu_objset_pool(dl->dl_os)->dp_empty_bpobj) {
203 		bpobj_enqueue_subobj(&dle->dle_bpobj, obj, tx);
204 	} else {
205 		bpobj_close(&dle->dle_bpobj);
206 		bpobj_decr_empty(dl->dl_os, tx);
207 		VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
208 		VERIFY3U(0, ==, zap_update_int_key(dl->dl_os, dl->dl_object,
209 		    dle->dle_mintxg, obj, tx));
210 	}
211 }
212 
213 void
214 dsl_deadlist_insert(dsl_deadlist_t *dl, const blkptr_t *bp, dmu_tx_t *tx)
215 {
216 	dsl_deadlist_entry_t dle_tofind;
217 	dsl_deadlist_entry_t *dle;
218 	avl_index_t where;
219 
220 	if (dl->dl_oldfmt) {
221 		bpobj_enqueue(&dl->dl_bpobj, bp, tx);
222 		return;
223 	}
224 
225 	dsl_deadlist_load_tree(dl);
226 
227 	dmu_buf_will_dirty(dl->dl_dbuf, tx);
228 	mutex_enter(&dl->dl_lock);
229 	dl->dl_phys->dl_used +=
230 	    bp_get_dsize_sync(dmu_objset_spa(dl->dl_os), bp);
231 	dl->dl_phys->dl_comp += BP_GET_PSIZE(bp);
232 	dl->dl_phys->dl_uncomp += BP_GET_UCSIZE(bp);
233 	mutex_exit(&dl->dl_lock);
234 
235 	dle_tofind.dle_mintxg = bp->blk_birth;
236 	dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
237 	if (dle == NULL)
238 		dle = avl_nearest(&dl->dl_tree, where, AVL_BEFORE);
239 	else
240 		dle = AVL_PREV(&dl->dl_tree, dle);
241 	dle_enqueue(dl, dle, bp, tx);
242 }
243 
244 /*
245  * Insert new key in deadlist, which must be > all current entries.
246  * mintxg is not inclusive.
247  */
248 void
249 dsl_deadlist_add_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx)
250 {
251 	uint64_t obj;
252 	dsl_deadlist_entry_t *dle;
253 
254 	if (dl->dl_oldfmt)
255 		return;
256 
257 	dsl_deadlist_load_tree(dl);
258 
259 	dle = kmem_alloc(sizeof (*dle), KM_SLEEP);
260 	dle->dle_mintxg = mintxg;
261 	obj = bpobj_alloc_empty(dl->dl_os, SPA_OLD_MAXBLOCKSIZE, tx);
262 	VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
263 	avl_add(&dl->dl_tree, dle);
264 
265 	VERIFY3U(0, ==, zap_add_int_key(dl->dl_os, dl->dl_object,
266 	    mintxg, obj, tx));
267 }
268 
269 /*
270  * Remove this key, merging its entries into the previous key.
271  */
272 void
273 dsl_deadlist_remove_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx)
274 {
275 	dsl_deadlist_entry_t dle_tofind;
276 	dsl_deadlist_entry_t *dle, *dle_prev;
277 
278 	if (dl->dl_oldfmt)
279 		return;
280 
281 	dsl_deadlist_load_tree(dl);
282 
283 	dle_tofind.dle_mintxg = mintxg;
284 	dle = avl_find(&dl->dl_tree, &dle_tofind, NULL);
285 	dle_prev = AVL_PREV(&dl->dl_tree, dle);
286 
287 	dle_enqueue_subobj(dl, dle_prev, dle->dle_bpobj.bpo_object, tx);
288 
289 	avl_remove(&dl->dl_tree, dle);
290 	bpobj_close(&dle->dle_bpobj);
291 	kmem_free(dle, sizeof (*dle));
292 
293 	VERIFY3U(0, ==, zap_remove_int(dl->dl_os, dl->dl_object, mintxg, tx));
294 }
295 
296 /*
297  * Walk ds's snapshots to regenerate generate ZAP & AVL.
298  */
299 static void
300 dsl_deadlist_regenerate(objset_t *os, uint64_t dlobj,
301     uint64_t mrs_obj, dmu_tx_t *tx)
302 {
303 	dsl_deadlist_t dl;
304 	dsl_pool_t *dp = dmu_objset_pool(os);
305 
306 	dsl_deadlist_open(&dl, os, dlobj);
307 	if (dl.dl_oldfmt) {
308 		dsl_deadlist_close(&dl);
309 		return;
310 	}
311 
312 	while (mrs_obj != 0) {
313 		dsl_dataset_t *ds;
314 		VERIFY3U(0, ==, dsl_dataset_hold_obj(dp, mrs_obj, FTAG, &ds));
315 		dsl_deadlist_add_key(&dl,
316 		    dsl_dataset_phys(ds)->ds_prev_snap_txg, tx);
317 		mrs_obj = dsl_dataset_phys(ds)->ds_prev_snap_obj;
318 		dsl_dataset_rele(ds, FTAG);
319 	}
320 	dsl_deadlist_close(&dl);
321 }
322 
323 uint64_t
324 dsl_deadlist_clone(dsl_deadlist_t *dl, uint64_t maxtxg,
325     uint64_t mrs_obj, dmu_tx_t *tx)
326 {
327 	dsl_deadlist_entry_t *dle;
328 	uint64_t newobj;
329 
330 	newobj = dsl_deadlist_alloc(dl->dl_os, tx);
331 
332 	if (dl->dl_oldfmt) {
333 		dsl_deadlist_regenerate(dl->dl_os, newobj, mrs_obj, tx);
334 		return (newobj);
335 	}
336 
337 	dsl_deadlist_load_tree(dl);
338 
339 	for (dle = avl_first(&dl->dl_tree); dle;
340 	    dle = AVL_NEXT(&dl->dl_tree, dle)) {
341 		uint64_t obj;
342 
343 		if (dle->dle_mintxg >= maxtxg)
344 			break;
345 
346 		obj = bpobj_alloc_empty(dl->dl_os, SPA_OLD_MAXBLOCKSIZE, tx);
347 		VERIFY3U(0, ==, zap_add_int_key(dl->dl_os, newobj,
348 		    dle->dle_mintxg, obj, tx));
349 	}
350 	return (newobj);
351 }
352 
353 void
354 dsl_deadlist_space(dsl_deadlist_t *dl,
355     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
356 {
357 	if (dl->dl_oldfmt) {
358 		VERIFY3U(0, ==, bpobj_space(&dl->dl_bpobj,
359 		    usedp, compp, uncompp));
360 		return;
361 	}
362 
363 	mutex_enter(&dl->dl_lock);
364 	*usedp = dl->dl_phys->dl_used;
365 	*compp = dl->dl_phys->dl_comp;
366 	*uncompp = dl->dl_phys->dl_uncomp;
367 	mutex_exit(&dl->dl_lock);
368 }
369 
370 /*
371  * return space used in the range (mintxg, maxtxg].
372  * Includes maxtxg, does not include mintxg.
373  * mintxg and maxtxg must both be keys in the deadlist (unless maxtxg is
374  * larger than any bp in the deadlist (eg. UINT64_MAX)).
375  */
376 void
377 dsl_deadlist_space_range(dsl_deadlist_t *dl, uint64_t mintxg, uint64_t maxtxg,
378     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
379 {
380 	dsl_deadlist_entry_t *dle;
381 	dsl_deadlist_entry_t dle_tofind;
382 	avl_index_t where;
383 
384 	if (dl->dl_oldfmt) {
385 		VERIFY3U(0, ==, bpobj_space_range(&dl->dl_bpobj,
386 		    mintxg, maxtxg, usedp, compp, uncompp));
387 		return;
388 	}
389 
390 	*usedp = *compp = *uncompp = 0;
391 
392 	mutex_enter(&dl->dl_lock);
393 	dsl_deadlist_load_tree(dl);
394 	dle_tofind.dle_mintxg = mintxg;
395 	dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
396 	/*
397 	 * If we don't find this mintxg, there shouldn't be anything
398 	 * after it either.
399 	 */
400 	ASSERT(dle != NULL ||
401 	    avl_nearest(&dl->dl_tree, where, AVL_AFTER) == NULL);
402 
403 	for (; dle && dle->dle_mintxg < maxtxg;
404 	    dle = AVL_NEXT(&dl->dl_tree, dle)) {
405 		uint64_t used, comp, uncomp;
406 
407 		VERIFY3U(0, ==, bpobj_space(&dle->dle_bpobj,
408 		    &used, &comp, &uncomp));
409 
410 		*usedp += used;
411 		*compp += comp;
412 		*uncompp += uncomp;
413 	}
414 	mutex_exit(&dl->dl_lock);
415 }
416 
417 static void
418 dsl_deadlist_insert_bpobj(dsl_deadlist_t *dl, uint64_t obj, uint64_t birth,
419     dmu_tx_t *tx)
420 {
421 	dsl_deadlist_entry_t dle_tofind;
422 	dsl_deadlist_entry_t *dle;
423 	avl_index_t where;
424 	uint64_t used, comp, uncomp;
425 	bpobj_t bpo;
426 
427 	VERIFY3U(0, ==, bpobj_open(&bpo, dl->dl_os, obj));
428 	VERIFY3U(0, ==, bpobj_space(&bpo, &used, &comp, &uncomp));
429 	bpobj_close(&bpo);
430 
431 	dsl_deadlist_load_tree(dl);
432 
433 	dmu_buf_will_dirty(dl->dl_dbuf, tx);
434 	mutex_enter(&dl->dl_lock);
435 	dl->dl_phys->dl_used += used;
436 	dl->dl_phys->dl_comp += comp;
437 	dl->dl_phys->dl_uncomp += uncomp;
438 	mutex_exit(&dl->dl_lock);
439 
440 	dle_tofind.dle_mintxg = birth;
441 	dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
442 	if (dle == NULL)
443 		dle = avl_nearest(&dl->dl_tree, where, AVL_BEFORE);
444 	dle_enqueue_subobj(dl, dle, obj, tx);
445 }
446 
447 static int
448 dsl_deadlist_insert_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
449 {
450 	dsl_deadlist_t *dl = arg;
451 	dsl_deadlist_insert(dl, bp, tx);
452 	return (0);
453 }
454 
455 /*
456  * Merge the deadlist pointed to by 'obj' into dl.  obj will be left as
457  * an empty deadlist.
458  */
459 void
460 dsl_deadlist_merge(dsl_deadlist_t *dl, uint64_t obj, dmu_tx_t *tx)
461 {
462 	zap_cursor_t zc;
463 	zap_attribute_t za;
464 	dmu_buf_t *bonus;
465 	dsl_deadlist_phys_t *dlp;
466 	dmu_object_info_t doi;
467 
468 	VERIFY3U(0, ==, dmu_object_info(dl->dl_os, obj, &doi));
469 	if (doi.doi_type == DMU_OT_BPOBJ) {
470 		bpobj_t bpo;
471 		VERIFY3U(0, ==, bpobj_open(&bpo, dl->dl_os, obj));
472 		VERIFY3U(0, ==, bpobj_iterate(&bpo,
473 		    dsl_deadlist_insert_cb, dl, tx));
474 		bpobj_close(&bpo);
475 		return;
476 	}
477 
478 	for (zap_cursor_init(&zc, dl->dl_os, obj);
479 	    zap_cursor_retrieve(&zc, &za) == 0;
480 	    zap_cursor_advance(&zc)) {
481 		uint64_t mintxg = strtonum(za.za_name, NULL);
482 		dsl_deadlist_insert_bpobj(dl, za.za_first_integer, mintxg, tx);
483 		VERIFY3U(0, ==, zap_remove_int(dl->dl_os, obj, mintxg, tx));
484 	}
485 	zap_cursor_fini(&zc);
486 
487 	VERIFY3U(0, ==, dmu_bonus_hold(dl->dl_os, obj, FTAG, &bonus));
488 	dlp = bonus->db_data;
489 	dmu_buf_will_dirty(bonus, tx);
490 	bzero(dlp, sizeof (*dlp));
491 	dmu_buf_rele(bonus, FTAG);
492 }
493 
494 /*
495  * Remove entries on dl that are >= mintxg, and put them on the bpobj.
496  */
497 void
498 dsl_deadlist_move_bpobj(dsl_deadlist_t *dl, bpobj_t *bpo, uint64_t mintxg,
499     dmu_tx_t *tx)
500 {
501 	dsl_deadlist_entry_t dle_tofind;
502 	dsl_deadlist_entry_t *dle;
503 	avl_index_t where;
504 
505 	ASSERT(!dl->dl_oldfmt);
506 	dmu_buf_will_dirty(dl->dl_dbuf, tx);
507 	dsl_deadlist_load_tree(dl);
508 
509 	dle_tofind.dle_mintxg = mintxg;
510 	dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
511 	if (dle == NULL)
512 		dle = avl_nearest(&dl->dl_tree, where, AVL_AFTER);
513 	while (dle) {
514 		uint64_t used, comp, uncomp;
515 		dsl_deadlist_entry_t *dle_next;
516 
517 		bpobj_enqueue_subobj(bpo, dle->dle_bpobj.bpo_object, tx);
518 
519 		VERIFY3U(0, ==, bpobj_space(&dle->dle_bpobj,
520 		    &used, &comp, &uncomp));
521 		mutex_enter(&dl->dl_lock);
522 		ASSERT3U(dl->dl_phys->dl_used, >=, used);
523 		ASSERT3U(dl->dl_phys->dl_comp, >=, comp);
524 		ASSERT3U(dl->dl_phys->dl_uncomp, >=, uncomp);
525 		dl->dl_phys->dl_used -= used;
526 		dl->dl_phys->dl_comp -= comp;
527 		dl->dl_phys->dl_uncomp -= uncomp;
528 		mutex_exit(&dl->dl_lock);
529 
530 		VERIFY3U(0, ==, zap_remove_int(dl->dl_os, dl->dl_object,
531 		    dle->dle_mintxg, tx));
532 
533 		dle_next = AVL_NEXT(&dl->dl_tree, dle);
534 		avl_remove(&dl->dl_tree, dle);
535 		bpobj_close(&dle->dle_bpobj);
536 		kmem_free(dle, sizeof (*dle));
537 		dle = dle_next;
538 	}
539 }
540