1 /*
2 * CDDL HEADER START
3 *
4 * This file and its contents are supplied under the terms of the
5 * Common Development and Distribution License ("CDDL"), version 1.0.
6 * You may only use this file in accordance with the terms of version
7 * 1.0 of the CDDL.
8 *
9 * A full copy of the text of the CDDL should have accompanied this
10 * source. A copy of the CDDL is also available via the Internet at
11 * http://www.illumos.org/license/CDDL.
12 *
13 * CDDL HEADER END
14 */
15
16 /*
17 * Copyright (c) 2015, 2017 by Delphix. All rights reserved.
18 */
19
20 #include <sys/dmu_tx.h>
21 #include <sys/dsl_pool.h>
22 #include <sys/spa.h>
23 #include <sys/vdev_impl.h>
24 #include <sys/vdev_indirect_mapping.h>
25 #include <sys/zfeature.h>
26 #include <sys/dmu_objset.h>
27
28 static boolean_t
29 vdev_indirect_mapping_verify(vdev_indirect_mapping_t *vim)
30 {
31 ASSERT(vim != NULL);
32
33 ASSERT(vim->vim_object != 0);
34 ASSERT(vim->vim_objset != NULL);
35 ASSERT(vim->vim_phys != NULL);
36 ASSERT(vim->vim_dbuf != NULL);
37
38 EQUIV(vim->vim_phys->vimp_num_entries > 0,
39 vim->vim_entries != NULL);
40 if (vim->vim_phys->vimp_num_entries > 0) {
41 vdev_indirect_mapping_entry_phys_t *last_entry =
42 &vim->vim_entries[vim->vim_phys->vimp_num_entries - 1];
43 uint64_t offset = DVA_MAPPING_GET_SRC_OFFSET(last_entry);
44 uint64_t size = DVA_GET_ASIZE(&last_entry->vimep_dst);
45
46 ASSERT3U(vim->vim_phys->vimp_max_offset, >=, offset + size);
47 }
48 if (vim->vim_havecounts) {
49 ASSERT(vim->vim_phys->vimp_counts_object != 0);
50 }
51
52 return (B_TRUE);
53 }
54
55 uint64_t
56 vdev_indirect_mapping_num_entries(vdev_indirect_mapping_t *vim)
57 {
58 ASSERT(vdev_indirect_mapping_verify(vim));
59
60 return (vim->vim_phys->vimp_num_entries);
61 }
62
63 uint64_t
64 vdev_indirect_mapping_max_offset(vdev_indirect_mapping_t *vim)
65 {
66 ASSERT(vdev_indirect_mapping_verify(vim));
67
68 return (vim->vim_phys->vimp_max_offset);
69 }
70
71 uint64_t
72 vdev_indirect_mapping_object(vdev_indirect_mapping_t *vim)
73 {
74 ASSERT(vdev_indirect_mapping_verify(vim));
75
76 return (vim->vim_object);
77 }
78
79 uint64_t
80 vdev_indirect_mapping_bytes_mapped(vdev_indirect_mapping_t *vim)
81 {
82 ASSERT(vdev_indirect_mapping_verify(vim));
83
84 return (vim->vim_phys->vimp_bytes_mapped);
85 }
86
87 /*
88 * The length (in bytes) of the mapping object array in memory and
89 * (logically) on disk.
90 *
91 * Note that unlike most of our accessor functions,
92 * we don't assert that the struct is consistent; therefore it can be
93 * called while there may be concurrent changes, if we don't care about
94 * the value being immediately stale (e.g. from spa_removal_get_stats()).
95 */
96 uint64_t
97 vdev_indirect_mapping_size(vdev_indirect_mapping_t *vim)
98 {
99 return (vim->vim_phys->vimp_num_entries * sizeof (*vim->vim_entries));
100 }
101
102 /*
103 * Compare an offset with an indirect mapping entry; there are three
104 * possible scenarios:
105 *
106 * 1. The offset is "less than" the mapping entry; meaning the
107 * offset is less than the source offset of the mapping entry. In
108 * this case, there is no overlap between the offset and the
109 * mapping entry and -1 will be returned.
110 *
111 * 2. The offset is "greater than" the mapping entry; meaning the
112 * offset is greater than the mapping entry's source offset plus
113 * the entry's size. In this case, there is no overlap between
114 * the offset and the mapping entry and 1 will be returned.
115 *
116 * NOTE: If the offset is actually equal to the entry's offset
117 * plus size, this is considered to be "greater" than the entry,
118 * and this case applies (i.e. 1 will be returned). Thus, the
119 * entry's "range" can be considered to be inclusive at its
120 * start, but exclusive at its end: e.g. [src, src + size).
121 *
122 * 3. The last case to consider is if the offset actually falls
123 * within the mapping entry's range. If this is the case, the
124 * offset is considered to be "equal to" the mapping entry and
125 * 0 will be returned.
126 *
127 * NOTE: If the offset is equal to the entry's source offset,
128 * this case applies and 0 will be returned. If the offset is
129 * equal to the entry's source plus its size, this case does
130 * *not* apply (see "NOTE" above for scenario 2), and 1 will be
131 * returned.
132 */
133 static int
134 dva_mapping_overlap_compare(const void *v_key, const void *v_array_elem)
135 {
136 const uint64_t *key = v_key;
137 const vdev_indirect_mapping_entry_phys_t *array_elem =
138 v_array_elem;
139 uint64_t src_offset = DVA_MAPPING_GET_SRC_OFFSET(array_elem);
140
141 if (*key < src_offset) {
142 return (-1);
143 } else if (*key < src_offset + DVA_GET_ASIZE(&array_elem->vimep_dst)) {
144 return (0);
145 } else {
146 return (1);
147 }
148 }
149
150 /*
151 * Returns the mapping entry for the given offset.
152 *
153 * It's possible that the given offset will not be in the mapping table
154 * (i.e. no mapping entries contain this offset), in which case, the
155 * return value value depends on the "next_if_missing" parameter.
156 *
157 * If the offset is not found in the table and "next_if_missing" is
158 * B_FALSE, then NULL will always be returned. The behavior is intended
159 * to allow consumers to get the entry corresponding to the offset
160 * parameter, iff the offset overlaps with an entry in the table.
161 *
162 * If the offset is not found in the table and "next_if_missing" is
163 * B_TRUE, then the entry nearest to the given offset will be returned,
164 * such that the entry's source offset is greater than the offset
165 * passed in (i.e. the "next" mapping entry in the table is returned, if
166 * the offset is missing from the table). If there are no entries whose
167 * source offset is greater than the passed in offset, NULL is returned.
168 */
169 static vdev_indirect_mapping_entry_phys_t *
170 vdev_indirect_mapping_entry_for_offset_impl(vdev_indirect_mapping_t *vim,
171 uint64_t offset, boolean_t next_if_missing)
172 {
173 ASSERT(vdev_indirect_mapping_verify(vim));
174 ASSERT(vim->vim_phys->vimp_num_entries > 0);
175
176 vdev_indirect_mapping_entry_phys_t *entry = NULL;
177
178 uint64_t last = vim->vim_phys->vimp_num_entries - 1;
179 uint64_t base = 0;
180
181 /*
182 * We don't define these inside of the while loop because we use
183 * their value in the case that offset isn't in the mapping.
184 */
185 uint64_t mid;
186 int result;
187
188 while (last >= base) {
189 mid = base + ((last - base) >> 1);
190
191 result = dva_mapping_overlap_compare(&offset,
192 &vim->vim_entries[mid]);
193
194 if (result == 0) {
195 entry = &vim->vim_entries[mid];
196 break;
197 } else if (result < 0) {
198 last = mid - 1;
199 } else {
200 base = mid + 1;
201 }
202 }
203
204 if (entry == NULL && next_if_missing) {
205 ASSERT3U(base, ==, last + 1);
206 ASSERT(mid == base || mid == last);
207 ASSERT3S(result, !=, 0);
208
209 /*
210 * The offset we're looking for isn't actually contained
211 * in the mapping table, thus we need to return the
212 * closest mapping entry that is greater than the
213 * offset. We reuse the result of the last comparison,
214 * comparing the mapping entry at index "mid" and the
215 * offset. The offset is guaranteed to lie between
216 * indices one less than "mid", and one greater than
217 * "mid"; we just need to determine if offset is greater
218 * than, or less than the mapping entry contained at
219 * index "mid".
220 */
221
222 uint64_t index;
223 if (result < 0)
224 index = mid;
225 else
226 index = mid + 1;
227
228 ASSERT3U(index, <=, vim->vim_phys->vimp_num_entries);
229
230 if (index == vim->vim_phys->vimp_num_entries) {
231 /*
232 * If "index" is past the end of the entries
233 * array, then not only is the offset not in the
234 * mapping table, but it's actually greater than
235 * all entries in the table. In this case, we
236 * can't return a mapping entry greater than the
237 * offset (since none exist), so we return NULL.
238 */
239
240 ASSERT3S(dva_mapping_overlap_compare(&offset,
241 &vim->vim_entries[index - 1]), >, 0);
242
243 return (NULL);
244 } else {
245 /*
246 * Just to be safe, we verify the offset falls
247 * in between the mapping entries at index and
248 * one less than index. Since we know the offset
249 * doesn't overlap an entry, and we're supposed
250 * to return the entry just greater than the
251 * offset, both of the following tests must be
252 * true.
253 */
254 ASSERT3S(dva_mapping_overlap_compare(&offset,
255 &vim->vim_entries[index]), <, 0);
256 IMPLY(index >= 1, dva_mapping_overlap_compare(&offset,
257 &vim->vim_entries[index - 1]) > 0);
258
259 return (&vim->vim_entries[index]);
260 }
261 } else {
262 return (entry);
263 }
264 }
265
266 vdev_indirect_mapping_entry_phys_t *
267 vdev_indirect_mapping_entry_for_offset(vdev_indirect_mapping_t *vim,
268 uint64_t offset)
269 {
270 return (vdev_indirect_mapping_entry_for_offset_impl(vim, offset,
271 B_FALSE));
272 }
273
274 vdev_indirect_mapping_entry_phys_t *
275 vdev_indirect_mapping_entry_for_offset_or_next(vdev_indirect_mapping_t *vim,
276 uint64_t offset)
277 {
278 return (vdev_indirect_mapping_entry_for_offset_impl(vim, offset,
279 B_TRUE));
280 }
281
282 void
283 vdev_indirect_mapping_close(vdev_indirect_mapping_t *vim)
284 {
285 ASSERT(vdev_indirect_mapping_verify(vim));
286
287 if (vim->vim_phys->vimp_num_entries > 0) {
288 uint64_t map_size = vdev_indirect_mapping_size(vim);
289 kmem_free(vim->vim_entries, map_size);
290 vim->vim_entries = NULL;
291 }
292
293 dmu_buf_rele(vim->vim_dbuf, vim);
294
295 vim->vim_objset = NULL;
296 vim->vim_object = 0;
297 vim->vim_dbuf = NULL;
298 vim->vim_phys = NULL;
299
300 kmem_free(vim, sizeof (*vim));
301 }
302
303 uint64_t
304 vdev_indirect_mapping_alloc(objset_t *os, dmu_tx_t *tx)
305 {
306 uint64_t object;
307 ASSERT(dmu_tx_is_syncing(tx));
308 uint64_t bonus_size = VDEV_INDIRECT_MAPPING_SIZE_V0;
309
310 if (spa_feature_is_enabled(os->os_spa, SPA_FEATURE_OBSOLETE_COUNTS)) {
311 bonus_size = sizeof (vdev_indirect_mapping_phys_t);
312 }
313
314 object = dmu_object_alloc(os,
315 DMU_OTN_UINT64_METADATA, SPA_OLD_MAXBLOCKSIZE,
316 DMU_OTN_UINT64_METADATA, bonus_size,
317 tx);
318
319 if (spa_feature_is_enabled(os->os_spa, SPA_FEATURE_OBSOLETE_COUNTS)) {
320 dmu_buf_t *dbuf;
321 vdev_indirect_mapping_phys_t *vimp;
322
323 VERIFY0(dmu_bonus_hold(os, object, FTAG, &dbuf));
324 dmu_buf_will_dirty(dbuf, tx);
325 vimp = dbuf->db_data;
326 vimp->vimp_counts_object = dmu_object_alloc(os,
327 DMU_OTN_UINT32_METADATA, SPA_OLD_MAXBLOCKSIZE,
328 DMU_OT_NONE, 0, tx);
329 spa_feature_incr(os->os_spa, SPA_FEATURE_OBSOLETE_COUNTS, tx);
330 dmu_buf_rele(dbuf, FTAG);
331 }
332
333 return (object);
334 }
335
336
337 vdev_indirect_mapping_t *
338 vdev_indirect_mapping_open(objset_t *os, uint64_t mapping_object)
339 {
340 vdev_indirect_mapping_t *vim = kmem_zalloc(sizeof (*vim), KM_SLEEP);
341 dmu_object_info_t doi;
342 VERIFY0(dmu_object_info(os, mapping_object, &doi));
343
344 vim->vim_objset = os;
345 vim->vim_object = mapping_object;
346
347 VERIFY0(dmu_bonus_hold(os, vim->vim_object, vim,
348 &vim->vim_dbuf));
349 vim->vim_phys = vim->vim_dbuf->db_data;
350
351 vim->vim_havecounts =
352 (doi.doi_bonus_size > VDEV_INDIRECT_MAPPING_SIZE_V0);
353
354 if (vim->vim_phys->vimp_num_entries > 0) {
355 uint64_t map_size = vdev_indirect_mapping_size(vim);
356 vim->vim_entries = kmem_alloc(map_size, KM_SLEEP);
357 VERIFY0(dmu_read(os, vim->vim_object, 0, map_size,
358 vim->vim_entries, DMU_READ_PREFETCH));
359 }
360
361 ASSERT(vdev_indirect_mapping_verify(vim));
362
363 return (vim);
364 }
365
366 void
367 vdev_indirect_mapping_free(objset_t *os, uint64_t object, dmu_tx_t *tx)
368 {
369 vdev_indirect_mapping_t *vim = vdev_indirect_mapping_open(os, object);
370 if (vim->vim_havecounts) {
371 VERIFY0(dmu_object_free(os, vim->vim_phys->vimp_counts_object,
372 tx));
373 spa_feature_decr(os->os_spa, SPA_FEATURE_OBSOLETE_COUNTS, tx);
374 }
375 vdev_indirect_mapping_close(vim);
376
377 VERIFY0(dmu_object_free(os, object, tx));
378 }
379
380 /*
381 * Append the list of vdev_indirect_mapping_entry_t's to the on-disk
382 * mapping object. Also remove the entries from the list and free them.
383 * This also implicitly extends the max_offset of the mapping (to the end
384 * of the last entry).
385 */
386 void
387 vdev_indirect_mapping_add_entries(vdev_indirect_mapping_t *vim,
388 list_t *list, dmu_tx_t *tx)
389 {
390 vdev_indirect_mapping_entry_phys_t *mapbuf;
391 uint64_t old_size;
392 uint32_t *countbuf = NULL;
393 vdev_indirect_mapping_entry_phys_t *old_entries;
394 uint64_t old_count;
395 uint64_t entries_written = 0;
396
397 ASSERT(vdev_indirect_mapping_verify(vim));
398 ASSERT(dmu_tx_is_syncing(tx));
399 ASSERT(dsl_pool_sync_context(dmu_tx_pool(tx)));
400 ASSERT(!list_is_empty(list));
401
402 old_size = vdev_indirect_mapping_size(vim);
403 old_entries = vim->vim_entries;
404 old_count = vim->vim_phys->vimp_num_entries;
405
406 dmu_buf_will_dirty(vim->vim_dbuf, tx);
407
408 mapbuf = zio_buf_alloc(SPA_OLD_MAXBLOCKSIZE);
409 if (vim->vim_havecounts) {
410 countbuf = zio_buf_alloc(SPA_OLD_MAXBLOCKSIZE);
411 ASSERT(spa_feature_is_active(vim->vim_objset->os_spa,
412 SPA_FEATURE_OBSOLETE_COUNTS));
413 }
414 while (!list_is_empty(list)) {
415 uint64_t i;
416 /*
417 * Write entries from the list to the
418 * vdev_im_object in batches of size SPA_OLD_MAXBLOCKSIZE.
419 */
420 for (i = 0; i < SPA_OLD_MAXBLOCKSIZE / sizeof (*mapbuf); i++) {
421 vdev_indirect_mapping_entry_t *entry =
422 list_remove_head(list);
423 if (entry == NULL)
424 break;
425
426 uint64_t size =
427 DVA_GET_ASIZE(&entry->vime_mapping.vimep_dst);
428 uint64_t src_offset =
429 DVA_MAPPING_GET_SRC_OFFSET(&entry->vime_mapping);
430
431 /*
432 * We shouldn't be adding an entry which is fully
433 * obsolete.
434 */
435 ASSERT3U(entry->vime_obsolete_count, <, size);
436 IMPLY(entry->vime_obsolete_count != 0,
437 vim->vim_havecounts);
438
439 mapbuf[i] = entry->vime_mapping;
440 if (vim->vim_havecounts)
441 countbuf[i] = entry->vime_obsolete_count;
442
443 vim->vim_phys->vimp_bytes_mapped += size;
444 ASSERT3U(src_offset, >=,
445 vim->vim_phys->vimp_max_offset);
446 vim->vim_phys->vimp_max_offset = src_offset + size;
447
448 entries_written++;
449
450 kmem_free(entry, sizeof (*entry));
451 }
452 dmu_write(vim->vim_objset, vim->vim_object,
453 vim->vim_phys->vimp_num_entries * sizeof (*mapbuf),
454 i * sizeof (*mapbuf),
455 mapbuf, tx);
456 if (vim->vim_havecounts) {
457 dmu_write(vim->vim_objset,
458 vim->vim_phys->vimp_counts_object,
459 vim->vim_phys->vimp_num_entries *
460 sizeof (*countbuf),
461 i * sizeof (*countbuf), countbuf, tx);
462 }
463 vim->vim_phys->vimp_num_entries += i;
464 }
465 zio_buf_free(mapbuf, SPA_OLD_MAXBLOCKSIZE);
466 if (vim->vim_havecounts)
467 zio_buf_free(countbuf, SPA_OLD_MAXBLOCKSIZE);
468
469 /*
470 * Update the entry array to reflect the new entries. First, copy
471 * over any old entries then read back the new entries we just wrote.
472 */
473 uint64_t new_size = vdev_indirect_mapping_size(vim);
474 ASSERT3U(new_size, >, old_size);
475 ASSERT3U(new_size - old_size, ==,
476 entries_written * sizeof (vdev_indirect_mapping_entry_phys_t));
477 vim->vim_entries = kmem_alloc(new_size, KM_SLEEP);
478 if (old_size > 0) {
479 bcopy(old_entries, vim->vim_entries, old_size);
480 kmem_free(old_entries, old_size);
481 }
482 VERIFY0(dmu_read(vim->vim_objset, vim->vim_object, old_size,
483 new_size - old_size, &vim->vim_entries[old_count],
484 DMU_READ_PREFETCH));
485
486 zfs_dbgmsg("txg %llu: wrote %llu entries to "
487 "indirect mapping obj %llu; max offset=0x%llx",
488 (u_longlong_t)dmu_tx_get_txg(tx),
489 (u_longlong_t)entries_written,
490 (u_longlong_t)vim->vim_object,
491 (u_longlong_t)vim->vim_phys->vimp_max_offset);
492 }
493
494 /*
495 * Increment the relevant counts for the specified offset and length.
496 * The counts array must be obtained from
497 * vdev_indirect_mapping_load_obsolete_counts().
498 */
499 void
500 vdev_indirect_mapping_increment_obsolete_count(vdev_indirect_mapping_t *vim,
501 uint64_t offset, uint64_t length, uint32_t *counts)
502 {
503 vdev_indirect_mapping_entry_phys_t *mapping;
504 uint64_t index;
505
506 mapping = vdev_indirect_mapping_entry_for_offset(vim, offset);
507
508 ASSERT(length > 0);
509 ASSERT3P(mapping, !=, NULL);
510
511 index = mapping - vim->vim_entries;
512
513 while (length > 0) {
514 ASSERT3U(index, <, vdev_indirect_mapping_num_entries(vim));
515
516 uint64_t size = DVA_GET_ASIZE(&mapping->vimep_dst);
517 uint64_t inner_offset = offset -
518 DVA_MAPPING_GET_SRC_OFFSET(mapping);
519 VERIFY3U(inner_offset, <, size);
520 uint64_t inner_size = MIN(length, size - inner_offset);
521
522 VERIFY3U(counts[index] + inner_size, <=, size);
523 counts[index] += inner_size;
524
525 offset += inner_size;
526 length -= inner_size;
527 mapping++;
528 index++;
529 }
530 }
531
532 typedef struct load_obsolete_space_map_arg {
533 vdev_indirect_mapping_t *losma_vim;
534 uint32_t *losma_counts;
535 } load_obsolete_space_map_arg_t;
536
537 static int
538 load_obsolete_sm_callback(space_map_entry_t *sme, void *arg)
539 {
540 load_obsolete_space_map_arg_t *losma = arg;
541 ASSERT3S(sme->sme_type, ==, SM_ALLOC);
542
543 vdev_indirect_mapping_increment_obsolete_count(losma->losma_vim,
544 sme->sme_offset, sme->sme_run, losma->losma_counts);
545
546 return (0);
547 }
548
549 /*
550 * Modify the counts (increment them) based on the spacemap.
551 */
552 void
553 vdev_indirect_mapping_load_obsolete_spacemap(vdev_indirect_mapping_t *vim,
554 uint32_t *counts, space_map_t *obsolete_space_sm)
555 {
556 load_obsolete_space_map_arg_t losma;
557 losma.losma_counts = counts;
558 losma.losma_vim = vim;
559 VERIFY0(space_map_iterate(obsolete_space_sm,
560 load_obsolete_sm_callback, &losma));
561 }
562
563 /*
564 * Read the obsolete counts from disk, returning them in an array.
565 */
566 uint32_t *
567 vdev_indirect_mapping_load_obsolete_counts(vdev_indirect_mapping_t *vim)
568 {
569 ASSERT(vdev_indirect_mapping_verify(vim));
570
571 uint64_t counts_size =
572 vim->vim_phys->vimp_num_entries * sizeof (uint32_t);
573 uint32_t *counts = kmem_alloc(counts_size, KM_SLEEP);
574 if (vim->vim_havecounts) {
575 VERIFY0(dmu_read(vim->vim_objset,
576 vim->vim_phys->vimp_counts_object,
577 0, counts_size,
578 counts, DMU_READ_PREFETCH));
579 } else {
580 bzero(counts, counts_size);
581 }
582 return (counts);
583 }
584
585 extern void
586 vdev_indirect_mapping_free_obsolete_counts(vdev_indirect_mapping_t *vim,
587 uint32_t *counts)
588 {
589 ASSERT(vdev_indirect_mapping_verify(vim));
590
591 kmem_free(counts, vim->vim_phys->vimp_num_entries * sizeof (uint32_t));
592 }