btrfs-progs: mute coverity warnings about deadcode
[platform/upstream/btrfs-progs.git] / chunk-recover.c
1 /*
2  * Copyright (C) 2013 FUJITSU LIMITED.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public
6  * License v2 as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public
14  * License along with this program; if not, write to the
15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16  * Boston, MA 021110-1307, USA.
17  */
18
19 #include "kerncompat.h"
20 #include "androidcompat.h"
21
22 #include <stdio.h>
23 #include <stdio_ext.h>
24 #include <stdlib.h>
25 #include <sys/types.h>
26 #include <sys/stat.h>
27 #include <fcntl.h>
28 #include <unistd.h>
29 #include <uuid/uuid.h>
30 #include <pthread.h>
31
32 #include "list.h"
33 #include "radix-tree.h"
34 #include "ctree.h"
35 #include "extent-cache.h"
36 #include "disk-io.h"
37 #include "volumes.h"
38 #include "transaction.h"
39 #include "crc32c.h"
40 #include "utils.h"
41 #include "btrfsck.h"
42 #include "commands.h"
43
44 struct recover_control {
45         int verbose;
46         int yes;
47
48         u16 csum_size;
49         u32 sectorsize;
50         u32 leafsize;
51         u64 generation;
52         u64 chunk_root_generation;
53
54         struct btrfs_fs_devices *fs_devices;
55
56         struct cache_tree chunk;
57         struct block_group_tree bg;
58         struct device_extent_tree devext;
59         struct cache_tree eb_cache;
60
61         struct list_head good_chunks;
62         struct list_head bad_chunks;
63         struct list_head rebuild_chunks;
64         struct list_head unrepaired_chunks;
65         pthread_mutex_t rc_lock;
66 };
67
68 struct extent_record {
69         struct cache_extent cache;
70         u64 generation;
71         u8 csum[BTRFS_CSUM_SIZE];
72         struct btrfs_device *devices[BTRFS_MAX_MIRRORS];
73         u64 offsets[BTRFS_MAX_MIRRORS];
74         int nmirrors;
75 };
76
77 struct device_scan {
78         struct recover_control *rc;
79         struct btrfs_device *dev;
80         int fd;
81         u64 bytenr;
82 };
83
84 static struct extent_record *btrfs_new_extent_record(struct extent_buffer *eb)
85 {
86         struct extent_record *rec;
87
88         rec = calloc(1, sizeof(*rec));
89         if (!rec) {
90                 fprintf(stderr, "Fail to allocate memory for extent record.\n");
91                 exit(1);
92         }
93
94         rec->cache.start = btrfs_header_bytenr(eb);
95         rec->cache.size = eb->len;
96         rec->generation = btrfs_header_generation(eb);
97         read_extent_buffer(eb, rec->csum, (unsigned long)btrfs_header_csum(eb),
98                            BTRFS_CSUM_SIZE);
99         return rec;
100 }
101
102 static int process_extent_buffer(struct cache_tree *eb_cache,
103                                  struct extent_buffer *eb,
104                                  struct btrfs_device *device, u64 offset)
105 {
106         struct extent_record *rec;
107         struct extent_record *exist;
108         struct cache_extent *cache;
109         int ret = 0;
110
111         rec = btrfs_new_extent_record(eb);
112         if (!rec->cache.size)
113                 goto free_out;
114 again:
115         cache = lookup_cache_extent(eb_cache,
116                                     rec->cache.start,
117                                     rec->cache.size);
118         if (cache) {
119                 exist = container_of(cache, struct extent_record, cache);
120
121                 if (exist->generation > rec->generation)
122                         goto free_out;
123                 if (exist->generation == rec->generation) {
124                         if (exist->cache.start != rec->cache.start ||
125                             exist->cache.size != rec->cache.size ||
126                             memcmp(exist->csum, rec->csum, BTRFS_CSUM_SIZE)) {
127                                 ret = -EEXIST;
128                         } else {
129                                 BUG_ON(exist->nmirrors >= BTRFS_MAX_MIRRORS);
130                                 exist->devices[exist->nmirrors] = device;
131                                 exist->offsets[exist->nmirrors] = offset;
132                                 exist->nmirrors++;
133                         }
134                         goto free_out;
135                 }
136                 remove_cache_extent(eb_cache, cache);
137                 free(exist);
138                 goto again;
139         }
140
141         rec->devices[0] = device;
142         rec->offsets[0] = offset;
143         rec->nmirrors++;
144         ret = insert_cache_extent(eb_cache, &rec->cache);
145         BUG_ON(ret);
146 out:
147         return ret;
148 free_out:
149         free(rec);
150         goto out;
151 }
152
153 static void free_extent_record(struct cache_extent *cache)
154 {
155         struct extent_record *er;
156
157         er = container_of(cache, struct extent_record, cache);
158         free(er);
159 }
160
161 FREE_EXTENT_CACHE_BASED_TREE(extent_record, free_extent_record);
162
163 static struct btrfs_chunk *create_chunk_item(struct chunk_record *record)
164 {
165         struct btrfs_chunk *ret;
166         struct btrfs_stripe *chunk_stripe;
167         int i;
168
169         if (!record || record->num_stripes == 0)
170                 return NULL;
171         ret = malloc(btrfs_chunk_item_size(record->num_stripes));
172         if (!ret)
173                 return NULL;
174         btrfs_set_stack_chunk_length(ret, record->length);
175         btrfs_set_stack_chunk_owner(ret, record->owner);
176         btrfs_set_stack_chunk_stripe_len(ret, record->stripe_len);
177         btrfs_set_stack_chunk_type(ret, record->type_flags);
178         btrfs_set_stack_chunk_io_align(ret, record->io_align);
179         btrfs_set_stack_chunk_io_width(ret, record->io_width);
180         btrfs_set_stack_chunk_sector_size(ret, record->sector_size);
181         btrfs_set_stack_chunk_num_stripes(ret, record->num_stripes);
182         btrfs_set_stack_chunk_sub_stripes(ret, record->sub_stripes);
183         for (i = 0, chunk_stripe = &ret->stripe; i < record->num_stripes;
184              i++, chunk_stripe++) {
185                 btrfs_set_stack_stripe_devid(chunk_stripe,
186                                 record->stripes[i].devid);
187                 btrfs_set_stack_stripe_offset(chunk_stripe,
188                                 record->stripes[i].offset);
189                 memcpy(chunk_stripe->dev_uuid, record->stripes[i].dev_uuid,
190                        BTRFS_UUID_SIZE);
191         }
192         return ret;
193 }
194
195 static void init_recover_control(struct recover_control *rc, int verbose,
196                 int yes)
197 {
198         memset(rc, 0, sizeof(struct recover_control));
199         cache_tree_init(&rc->chunk);
200         cache_tree_init(&rc->eb_cache);
201         block_group_tree_init(&rc->bg);
202         device_extent_tree_init(&rc->devext);
203
204         INIT_LIST_HEAD(&rc->good_chunks);
205         INIT_LIST_HEAD(&rc->bad_chunks);
206         INIT_LIST_HEAD(&rc->rebuild_chunks);
207         INIT_LIST_HEAD(&rc->unrepaired_chunks);
208
209         rc->verbose = verbose;
210         rc->yes = yes;
211         pthread_mutex_init(&rc->rc_lock, NULL);
212 }
213
214 static void free_recover_control(struct recover_control *rc)
215 {
216         free_block_group_tree(&rc->bg);
217         free_chunk_cache_tree(&rc->chunk);
218         free_device_extent_tree(&rc->devext);
219         free_extent_record_tree(&rc->eb_cache);
220         pthread_mutex_destroy(&rc->rc_lock);
221 }
222
223 static int process_block_group_item(struct block_group_tree *bg_cache,
224                                     struct extent_buffer *leaf,
225                                     struct btrfs_key *key, int slot)
226 {
227         struct block_group_record *rec;
228         struct block_group_record *exist;
229         struct cache_extent *cache;
230         int ret = 0;
231
232         rec = btrfs_new_block_group_record(leaf, key, slot);
233         if (!rec->cache.size)
234                 goto free_out;
235 again:
236         cache = lookup_cache_extent(&bg_cache->tree,
237                                     rec->cache.start,
238                                     rec->cache.size);
239         if (cache) {
240                 exist = container_of(cache, struct block_group_record, cache);
241
242                 /*check the generation and replace if needed*/
243                 if (exist->generation > rec->generation)
244                         goto free_out;
245                 if (exist->generation == rec->generation) {
246                         int offset = offsetof(struct block_group_record,
247                                               generation);
248                         /*
249                          * According to the current kernel code, the following
250                          * case is impossble, or there is something wrong in
251                          * the kernel code.
252                          */
253                         if (memcmp(((void *)exist) + offset,
254                                    ((void *)rec) + offset,
255                                    sizeof(*rec) - offset))
256                                 ret = -EEXIST;
257                         goto free_out;
258                 }
259                 remove_cache_extent(&bg_cache->tree, cache);
260                 list_del_init(&exist->list);
261                 free(exist);
262                 /*
263                  * We must do search again to avoid the following cache.
264                  * /--old bg 1--//--old bg 2--/
265                  *        /--new bg--/
266                  */
267                 goto again;
268         }
269
270         ret = insert_block_group_record(bg_cache, rec);
271         BUG_ON(ret);
272 out:
273         return ret;
274 free_out:
275         free(rec);
276         goto out;
277 }
278
279 static int process_chunk_item(struct cache_tree *chunk_cache,
280                               struct extent_buffer *leaf, struct btrfs_key *key,
281                               int slot)
282 {
283         struct chunk_record *rec;
284         struct chunk_record *exist;
285         struct cache_extent *cache;
286         int ret = 0;
287
288         rec = btrfs_new_chunk_record(leaf, key, slot);
289         if (!rec->cache.size)
290                 goto free_out;
291 again:
292         cache = lookup_cache_extent(chunk_cache, rec->offset, rec->length);
293         if (cache) {
294                 exist = container_of(cache, struct chunk_record, cache);
295
296                 if (exist->generation > rec->generation)
297                         goto free_out;
298                 if (exist->generation == rec->generation) {
299                         int num_stripes = rec->num_stripes;
300                         int rec_size = btrfs_chunk_record_size(num_stripes);
301                         int offset = offsetof(struct chunk_record, generation);
302
303                         if (exist->num_stripes != rec->num_stripes ||
304                             memcmp(((void *)exist) + offset,
305                                    ((void *)rec) + offset,
306                                    rec_size - offset))
307                                 ret = -EEXIST;
308                         goto free_out;
309                 }
310                 remove_cache_extent(chunk_cache, cache);
311                 free(exist);
312                 goto again;
313         }
314         ret = insert_cache_extent(chunk_cache, &rec->cache);
315         BUG_ON(ret);
316 out:
317         return ret;
318 free_out:
319         free(rec);
320         goto out;
321 }
322
323 static int process_device_extent_item(struct device_extent_tree *devext_cache,
324                                       struct extent_buffer *leaf,
325                                       struct btrfs_key *key, int slot)
326 {
327         struct device_extent_record *rec;
328         struct device_extent_record *exist;
329         struct cache_extent *cache;
330         int ret = 0;
331
332         rec = btrfs_new_device_extent_record(leaf, key, slot);
333         if (!rec->cache.size)
334                 goto free_out;
335 again:
336         cache = lookup_cache_extent2(&devext_cache->tree,
337                                      rec->cache.objectid,
338                                      rec->cache.start,
339                                      rec->cache.size);
340         if (cache) {
341                 exist = container_of(cache, struct device_extent_record, cache);
342                 if (exist->generation > rec->generation)
343                         goto free_out;
344                 if (exist->generation == rec->generation) {
345                         int offset = offsetof(struct device_extent_record,
346                                               generation);
347                         if (memcmp(((void *)exist) + offset,
348                                    ((void *)rec) + offset,
349                                    sizeof(*rec) - offset))
350                                 ret = -EEXIST;
351                         goto free_out;
352                 }
353                 remove_cache_extent(&devext_cache->tree, cache);
354                 list_del_init(&exist->chunk_list);
355                 list_del_init(&exist->device_list);
356                 free(exist);
357                 goto again;
358         }
359
360         ret = insert_device_extent_record(devext_cache, rec);
361         BUG_ON(ret);
362 out:
363         return ret;
364 free_out:
365         free(rec);
366         goto out;
367 }
368
369 static void print_block_group_info(struct block_group_record *rec, char *prefix)
370 {
371         if (prefix)
372                 printf("%s", prefix);
373         printf("Block Group: start = %llu, len = %llu, flag = %llx\n",
374                rec->objectid, rec->offset, rec->flags);
375 }
376
377 static void print_block_group_tree(struct block_group_tree *tree)
378 {
379         struct cache_extent *cache;
380         struct block_group_record *rec;
381
382         printf("All Block Groups:\n");
383         for (cache = first_cache_extent(&tree->tree); cache;
384              cache = next_cache_extent(cache)) {
385                 rec = container_of(cache, struct block_group_record, cache);
386                 print_block_group_info(rec, "\t");
387         }
388         printf("\n");
389 }
390
391 static void print_stripe_info(struct stripe *data, char *prefix1, char *prefix2,
392                               int index)
393 {
394         if (prefix1)
395                 printf("%s", prefix1);
396         if (prefix2)
397                 printf("%s", prefix2);
398         printf("[%2d] Stripe: devid = %llu, offset = %llu\n",
399                index, data->devid, data->offset);
400 }
401
402 static void print_chunk_self_info(struct chunk_record *rec, char *prefix)
403 {
404         int i;
405
406         if (prefix)
407                 printf("%s", prefix);
408         printf("Chunk: start = %llu, len = %llu, type = %llx, num_stripes = %u\n",
409                rec->offset, rec->length, rec->type_flags, rec->num_stripes);
410         if (prefix)
411                 printf("%s", prefix);
412         printf("    Stripes list:\n");
413         for (i = 0; i < rec->num_stripes; i++)
414                 print_stripe_info(&rec->stripes[i], prefix, "    ", i);
415 }
416
417 static void print_chunk_tree(struct cache_tree *tree)
418 {
419         struct cache_extent *n;
420         struct chunk_record *entry;
421
422         printf("All Chunks:\n");
423         for (n = first_cache_extent(tree); n;
424              n = next_cache_extent(n)) {
425                 entry = container_of(n, struct chunk_record, cache);
426                 print_chunk_self_info(entry, "\t");
427         }
428         printf("\n");
429 }
430
431 static void print_device_extent_info(struct device_extent_record *rec,
432                                      char *prefix)
433 {
434         if (prefix)
435                 printf("%s", prefix);
436         printf("Device extent: devid = %llu, start = %llu, len = %llu, chunk offset = %llu\n",
437                rec->objectid, rec->offset, rec->length, rec->chunk_offset);
438 }
439
440 static void print_device_extent_tree(struct device_extent_tree *tree)
441 {
442         struct cache_extent *n;
443         struct device_extent_record *entry;
444
445         printf("All Device Extents:\n");
446         for (n = first_cache_extent(&tree->tree); n;
447              n = next_cache_extent(n)) {
448                 entry = container_of(n, struct device_extent_record, cache);
449                 print_device_extent_info(entry, "\t");
450         }
451         printf("\n");
452 }
453
454 static void print_device_info(struct btrfs_device *device, char *prefix)
455 {
456         if (prefix)
457                 printf("%s", prefix);
458         printf("Device: id = %llu, name = %s\n",
459                device->devid, device->name);
460 }
461
462 static void print_all_devices(struct list_head *devices)
463 {
464         struct btrfs_device *dev;
465
466         printf("All Devices:\n");
467         list_for_each_entry(dev, devices, dev_list)
468                 print_device_info(dev, "\t");
469         printf("\n");
470 }
471
472 static void print_scan_result(struct recover_control *rc)
473 {
474         if (!rc->verbose)
475                 return;
476
477         printf("DEVICE SCAN RESULT:\n");
478         printf("Filesystem Information:\n");
479         printf("\tsectorsize: %d\n", rc->sectorsize);
480         printf("\tleafsize: %d\n", rc->leafsize);
481         printf("\ttree root generation: %llu\n", rc->generation);
482         printf("\tchunk root generation: %llu\n", rc->chunk_root_generation);
483         printf("\n");
484
485         print_all_devices(&rc->fs_devices->devices);
486         print_block_group_tree(&rc->bg);
487         print_chunk_tree(&rc->chunk);
488         print_device_extent_tree(&rc->devext);
489 }
490
491 static void print_chunk_info(struct chunk_record *chunk, char *prefix)
492 {
493         struct device_extent_record *devext;
494         int i;
495
496         print_chunk_self_info(chunk, prefix);
497         if (prefix)
498                 printf("%s", prefix);
499         if (chunk->bg_rec)
500                 print_block_group_info(chunk->bg_rec, "    ");
501         else
502                 printf("    No block group.\n");
503         if (prefix)
504                 printf("%s", prefix);
505         if (list_empty(&chunk->dextents)) {
506                 printf("    No device extent.\n");
507         } else {
508                 printf("    Device extent list:\n");
509                 i = 0;
510                 list_for_each_entry(devext, &chunk->dextents, chunk_list) {
511                         if (prefix)
512                                 printf("%s", prefix);
513                         printf("%s[%2d]", "        ", i);
514                         print_device_extent_info(devext, NULL);
515                         i++;
516                 }
517         }
518 }
519
520 static void print_check_result(struct recover_control *rc)
521 {
522         struct chunk_record *chunk;
523         struct block_group_record *bg;
524         struct device_extent_record *devext;
525         int total = 0;
526         int good = 0;
527         int bad = 0;
528
529         if (!rc->verbose)
530                 return;
531
532         printf("CHECK RESULT:\n");
533         printf("Recoverable Chunks:\n");
534         list_for_each_entry(chunk, &rc->good_chunks, list) {
535                 print_chunk_info(chunk, "  ");
536                 good++;
537                 total++;
538         }
539         list_for_each_entry(chunk, &rc->rebuild_chunks, list) {
540                 print_chunk_info(chunk, "  ");
541                 good++;
542                 total++;
543         }
544         list_for_each_entry(chunk, &rc->unrepaired_chunks, list) {
545                 print_chunk_info(chunk, "  ");
546                 good++;
547                 total++;
548         }
549         printf("Unrecoverable Chunks:\n");
550         list_for_each_entry(chunk, &rc->bad_chunks, list) {
551                 print_chunk_info(chunk, "  ");
552                 bad++;
553                 total++;
554         }
555         printf("\n");
556         printf("Total Chunks:\t\t%d\n", total);
557         printf("  Recoverable:\t\t%d\n", good);
558         printf("  Unrecoverable:\t%d\n", bad);
559
560         printf("\n");
561         printf("Orphan Block Groups:\n");
562         list_for_each_entry(bg, &rc->bg.block_groups, list)
563                 print_block_group_info(bg, "  ");
564
565         printf("\n");
566         printf("Orphan Device Extents:\n");
567         list_for_each_entry(devext, &rc->devext.no_chunk_orphans, chunk_list)
568                 print_device_extent_info(devext, "  ");
569         printf("\n");
570 }
571
572 static int check_chunk_by_metadata(struct recover_control *rc,
573                                    struct btrfs_root *root,
574                                    struct chunk_record *chunk, int bg_only)
575 {
576         int ret;
577         int i;
578         int slot;
579         struct btrfs_path path;
580         struct btrfs_key key;
581         struct btrfs_root *dev_root;
582         struct stripe *stripe;
583         struct btrfs_dev_extent *dev_extent;
584         struct btrfs_block_group_item *bg_ptr;
585         struct extent_buffer *l;
586
587         btrfs_init_path(&path);
588
589         if (bg_only)
590                 goto bg_check;
591
592         dev_root = root->fs_info->dev_root;
593         for (i = 0; i < chunk->num_stripes; i++) {
594                 stripe = &chunk->stripes[i];
595
596                 key.objectid = stripe->devid;
597                 key.offset = stripe->offset;
598                 key.type = BTRFS_DEV_EXTENT_KEY;
599
600                 ret = btrfs_search_slot(NULL, dev_root, &key, &path, 0, 0);
601                 if (ret < 0) {
602                         fprintf(stderr, "Search device extent failed(%d)\n",
603                                 ret);
604                         btrfs_release_path(&path);
605                         return ret;
606                 } else if (ret > 0) {
607                         if (rc->verbose)
608                                 fprintf(stderr,
609                                         "No device extent[%llu, %llu]\n",
610                                         stripe->devid, stripe->offset);
611                         btrfs_release_path(&path);
612                         return -ENOENT;
613                 }
614                 l = path.nodes[0];
615                 slot = path.slots[0];
616                 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
617                 if (chunk->offset !=
618                     btrfs_dev_extent_chunk_offset(l, dev_extent)) {
619                         if (rc->verbose)
620                                 fprintf(stderr,
621                                         "Device tree unmatch with chunks dev_extent[%llu, %llu], chunk[%llu, %llu]\n",
622                                         btrfs_dev_extent_chunk_offset(l,
623                                                                 dev_extent),
624                                         btrfs_dev_extent_length(l, dev_extent),
625                                         chunk->offset, chunk->length);
626                         btrfs_release_path(&path);
627                         return -ENOENT;
628                 }
629                 btrfs_release_path(&path);
630         }
631
632 bg_check:
633         key.objectid = chunk->offset;
634         key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
635         key.offset = chunk->length;
636
637         ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, &path,
638                                 0, 0);
639         if (ret < 0) {
640                 fprintf(stderr, "Search block group failed(%d)\n", ret);
641                 btrfs_release_path(&path);
642                 return ret;
643         } else if (ret > 0) {
644                 if (rc->verbose)
645                         fprintf(stderr, "No block group[%llu, %llu]\n",
646                                 key.objectid, key.offset);
647                 btrfs_release_path(&path);
648                 return -ENOENT;
649         }
650
651         l = path.nodes[0];
652         slot = path.slots[0];
653         bg_ptr = btrfs_item_ptr(l, slot, struct btrfs_block_group_item);
654         if (chunk->type_flags != btrfs_disk_block_group_flags(l, bg_ptr)) {
655                 if (rc->verbose)
656                         fprintf(stderr,
657                                 "Chunk[%llu, %llu]'s type(%llu) is differemt with Block Group's type(%llu)\n",
658                                 chunk->offset, chunk->length, chunk->type_flags,
659                                 btrfs_disk_block_group_flags(l, bg_ptr));
660                 btrfs_release_path(&path);
661                 return -ENOENT;
662         }
663         btrfs_release_path(&path);
664         return 0;
665 }
666
667 static int check_all_chunks_by_metadata(struct recover_control *rc,
668                                         struct btrfs_root *root)
669 {
670         struct chunk_record *chunk;
671         struct chunk_record *next;
672         LIST_HEAD(orphan_chunks);
673         int ret = 0;
674         int err;
675
676         list_for_each_entry_safe(chunk, next, &rc->good_chunks, list) {
677                 err = check_chunk_by_metadata(rc, root, chunk, 0);
678                 if (err) {
679                         if (err == -ENOENT)
680                                 list_move_tail(&chunk->list, &orphan_chunks);
681                         else if (err && !ret)
682                                 ret = err;
683                 }
684         }
685
686         list_for_each_entry_safe(chunk, next, &rc->unrepaired_chunks, list) {
687                 err = check_chunk_by_metadata(rc, root, chunk, 1);
688                 if (err == -ENOENT)
689                         list_move_tail(&chunk->list, &orphan_chunks);
690                 else if (err && !ret)
691                         ret = err;
692         }
693
694         list_for_each_entry(chunk, &rc->bad_chunks, list) {
695                 err = check_chunk_by_metadata(rc, root, chunk, 1);
696                 if (err != -ENOENT && !ret)
697                         ret = err ? err : -EINVAL;
698         }
699         list_splice(&orphan_chunks, &rc->bad_chunks);
700         return ret;
701 }
702
703 static int extract_metadata_record(struct recover_control *rc,
704                                    struct extent_buffer *leaf)
705 {
706         struct btrfs_key key;
707         int ret = 0;
708         int i;
709         u32 nritems;
710
711         nritems = btrfs_header_nritems(leaf);
712         for (i = 0; i < nritems; i++) {
713                 btrfs_item_key_to_cpu(leaf, &key, i);
714                 switch (key.type) {
715                 case BTRFS_BLOCK_GROUP_ITEM_KEY:
716                         pthread_mutex_lock(&rc->rc_lock);
717                         ret = process_block_group_item(&rc->bg, leaf, &key, i);
718                         pthread_mutex_unlock(&rc->rc_lock);
719                         break;
720                 case BTRFS_CHUNK_ITEM_KEY:
721                         pthread_mutex_lock(&rc->rc_lock);
722                         ret = process_chunk_item(&rc->chunk, leaf, &key, i);
723                         pthread_mutex_unlock(&rc->rc_lock);
724                         break;
725                 case BTRFS_DEV_EXTENT_KEY:
726                         pthread_mutex_lock(&rc->rc_lock);
727                         ret = process_device_extent_item(&rc->devext, leaf,
728                                                          &key, i);
729                         pthread_mutex_unlock(&rc->rc_lock);
730                         break;
731                 }
732                 if (ret)
733                         break;
734         }
735         return ret;
736 }
737
738 static inline int is_super_block_address(u64 offset)
739 {
740         int i;
741
742         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
743                 if (offset == btrfs_sb_offset(i))
744                         return 1;
745         }
746         return 0;
747 }
748
749 static int scan_one_device(void *dev_scan_struct)
750 {
751         struct extent_buffer *buf;
752         u64 bytenr;
753         int ret = 0;
754         struct device_scan *dev_scan = (struct device_scan *)dev_scan_struct;
755         struct recover_control *rc = dev_scan->rc;
756         struct btrfs_device *device = dev_scan->dev;
757         int fd = dev_scan->fd;
758         int oldtype;
759
760         ret = pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, &oldtype);
761         if (ret)
762                 return 1;
763
764         buf = malloc(sizeof(*buf) + rc->leafsize);
765         if (!buf)
766                 return -ENOMEM;
767         buf->len = rc->leafsize;
768
769         bytenr = 0;
770         while (1) {
771                 dev_scan->bytenr = bytenr;
772
773                 if (is_super_block_address(bytenr))
774                         bytenr += rc->sectorsize;
775
776                 if (pread64(fd, buf->data, rc->leafsize, bytenr) <
777                     rc->leafsize)
778                         break;
779
780                 if (memcmp_extent_buffer(buf, rc->fs_devices->fsid,
781                                          btrfs_header_fsid(),
782                                          BTRFS_FSID_SIZE)) {
783                         bytenr += rc->sectorsize;
784                         continue;
785                 }
786
787                 if (verify_tree_block_csum_silent(buf, rc->csum_size)) {
788                         bytenr += rc->sectorsize;
789                         continue;
790                 }
791
792                 pthread_mutex_lock(&rc->rc_lock);
793                 ret = process_extent_buffer(&rc->eb_cache, buf, device, bytenr);
794                 pthread_mutex_unlock(&rc->rc_lock);
795                 if (ret)
796                         goto out;
797
798                 if (btrfs_header_level(buf) != 0)
799                         goto next_node;
800
801                 switch (btrfs_header_owner(buf)) {
802                 case BTRFS_EXTENT_TREE_OBJECTID:
803                 case BTRFS_DEV_TREE_OBJECTID:
804                         /* different tree use different generation */
805                         if (btrfs_header_generation(buf) > rc->generation)
806                                 break;
807                         ret = extract_metadata_record(rc, buf);
808                         if (ret)
809                                 goto out;
810                         break;
811                 case BTRFS_CHUNK_TREE_OBJECTID:
812                         if (btrfs_header_generation(buf) >
813                             rc->chunk_root_generation)
814                                 break;
815                         ret = extract_metadata_record(rc, buf);
816                         if (ret)
817                                 goto out;
818                         break;
819                 }
820 next_node:
821                 bytenr += rc->leafsize;
822         }
823 out:
824         close(fd);
825         free(buf);
826         return ret;
827 }
828
829 static int scan_devices(struct recover_control *rc)
830 {
831         int ret = 0;
832         int fd;
833         struct btrfs_device *dev;
834         struct device_scan *dev_scans;
835         pthread_t *t_scans;
836         long *t_rets;
837         int devnr = 0;
838         int devidx = 0;
839         int i;
840         int all_done;
841
842         list_for_each_entry(dev, &rc->fs_devices->devices, dev_list)
843                 devnr++;
844         dev_scans = (struct device_scan *)malloc(sizeof(struct device_scan)
845                                                  * devnr);
846         if (!dev_scans)
847                 return -ENOMEM;
848         t_scans = (pthread_t *)malloc(sizeof(pthread_t) * devnr);
849         if (!t_scans) {
850                 free(dev_scans);
851                 return -ENOMEM;
852         }
853         t_rets = (long *)malloc(sizeof(long) * devnr);
854         if (!t_rets) {
855                 free(dev_scans);
856                 free(t_scans);
857                 return -ENOMEM;
858         }
859
860         list_for_each_entry(dev, &rc->fs_devices->devices, dev_list) {
861                 fd = open(dev->name, O_RDONLY);
862                 if (fd < 0) {
863                         fprintf(stderr, "Failed to open device %s\n",
864                                 dev->name);
865                         ret = 1;
866                         goto out2;
867                 }
868                 dev_scans[devidx].rc = rc;
869                 dev_scans[devidx].dev = dev;
870                 dev_scans[devidx].fd = fd;
871                 dev_scans[devidx].bytenr = -1;
872                 devidx++;
873         }
874
875         for (i = 0; i < devidx; i++) {
876                 ret = pthread_create(&t_scans[i], NULL,
877                                      (void *)scan_one_device,
878                                      (void *)&dev_scans[i]);
879                 if (ret)
880                         goto out1;
881
882                 dev_scans[i].bytenr = 0;
883         }
884
885         while (1) {
886                 all_done = 1;
887                 for (i = 0; i < devidx; i++) {
888                         if (dev_scans[i].bytenr == -1)
889                                 continue;
890                         ret = pthread_tryjoin_np(t_scans[i],
891                                                  (void **)&t_rets[i]);
892                         if (ret == EBUSY) {
893                                 all_done = 0;
894                                 continue;
895                         }
896                         if (ret || t_rets[i]) {
897                                 ret = 1;
898                                 goto out1;
899                         }
900                         dev_scans[i].bytenr = -1;
901                 }
902
903                 printf("\rScanning: ");
904                 for (i = 0; i < devidx; i++) {
905                         if (dev_scans[i].bytenr == -1)
906                                 printf("%sDONE in dev%d",
907                                        i ? ", " : "", i);
908                         else
909                                 printf("%s%llu in dev%d",
910                                        i ? ", " : "", dev_scans[i].bytenr, i);
911                 }
912                 /* clear chars if exist in tail */
913                 printf("                ");
914                 printf("\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b");
915                 fflush(stdout);
916
917                 if (all_done) {
918                         printf("\n");
919                         break;
920                 }
921
922                 sleep(1);
923         }
924 out1:
925         for (i = 0; i < devidx; i++) {
926                 if (dev_scans[i].bytenr == -1)
927                         continue;
928                 pthread_cancel(t_scans[i]);
929         }
930 out2:
931         free(dev_scans);
932         free(t_scans);
933         free(t_rets);
934         return !!ret;
935 }
936
937 static int build_device_map_by_chunk_record(struct btrfs_root *root,
938                                             struct chunk_record *chunk)
939 {
940         int ret = 0;
941         int i;
942         u64 devid;
943         u8 uuid[BTRFS_UUID_SIZE];
944         u16 num_stripes;
945         struct btrfs_mapping_tree *map_tree;
946         struct map_lookup *map;
947         struct stripe *stripe;
948
949         map_tree = &root->fs_info->mapping_tree;
950         num_stripes = chunk->num_stripes;
951         map = malloc(btrfs_map_lookup_size(num_stripes));
952         if (!map)
953                 return -ENOMEM;
954         map->ce.start = chunk->offset;
955         map->ce.size = chunk->length;
956         map->num_stripes = num_stripes;
957         map->io_width = chunk->io_width;
958         map->io_align = chunk->io_align;
959         map->sector_size = chunk->sector_size;
960         map->stripe_len = chunk->stripe_len;
961         map->type = chunk->type_flags;
962         map->sub_stripes = chunk->sub_stripes;
963
964         for (i = 0, stripe = chunk->stripes; i < num_stripes; i++, stripe++) {
965                 devid = stripe->devid;
966                 memcpy(uuid, stripe->dev_uuid, BTRFS_UUID_SIZE);
967                 map->stripes[i].physical = stripe->offset;
968                 map->stripes[i].dev = btrfs_find_device(root, devid,
969                                                         uuid, NULL);
970                 if (!map->stripes[i].dev) {
971                         kfree(map);
972                         return -EIO;
973                 }
974         }
975
976         ret = insert_cache_extent(&map_tree->cache_tree, &map->ce);
977         return ret;
978 }
979
980 static int build_device_maps_by_chunk_records(struct recover_control *rc,
981                                               struct btrfs_root *root)
982 {
983         int ret = 0;
984         struct chunk_record *chunk;
985
986         list_for_each_entry(chunk, &rc->good_chunks, list) {
987                 ret = build_device_map_by_chunk_record(root, chunk);
988                 if (ret)
989                         return ret;
990         }
991         list_for_each_entry(chunk, &rc->rebuild_chunks, list) {
992                 ret = build_device_map_by_chunk_record(root, chunk);
993                 if (ret)
994                         return ret;
995         }
996         return ret;
997 }
998
999 static int block_group_remove_all_extent_items(struct btrfs_trans_handle *trans,
1000                                                struct btrfs_root *root,
1001                                                struct block_group_record *bg)
1002 {
1003         struct btrfs_fs_info *fs_info = root->fs_info;
1004         struct btrfs_key key;
1005         struct btrfs_path path;
1006         struct extent_buffer *leaf;
1007         u64 start = bg->objectid;
1008         u64 end = bg->objectid + bg->offset;
1009         u64 old_val;
1010         int nitems;
1011         int ret;
1012         int i;
1013         int del_s, del_nr;
1014
1015         btrfs_init_path(&path);
1016         root = root->fs_info->extent_root;
1017
1018         key.objectid = start;
1019         key.offset = 0;
1020         key.type = BTRFS_EXTENT_ITEM_KEY;
1021 again:
1022         ret = btrfs_search_slot(trans, root, &key, &path, -1, 1);
1023         if (ret < 0)
1024                 goto err;
1025         else if (ret > 0)
1026                 ret = 0;
1027
1028         leaf = path.nodes[0];
1029         nitems = btrfs_header_nritems(leaf);
1030         if (!nitems) {
1031                 /* The tree is empty. */
1032                 ret = 0;
1033                 goto err;
1034         }
1035
1036         if (path.slots[0] >= nitems) {
1037                 ret = btrfs_next_leaf(root, &path);
1038                 if (ret < 0)
1039                         goto err;
1040                 if (ret > 0) {
1041                         ret = 0;
1042                         goto err;
1043                 }
1044                 leaf = path.nodes[0];
1045                 btrfs_item_key_to_cpu(leaf, &key, 0);
1046                 if (key.objectid >= end)
1047                         goto err;
1048                 btrfs_release_path(&path);
1049                 goto again;
1050         }
1051
1052         del_nr = 0;
1053         del_s = -1;
1054         for (i = path.slots[0]; i < nitems; i++) {
1055                 btrfs_item_key_to_cpu(leaf, &key, i);
1056                 if (key.objectid >= end)
1057                         break;
1058
1059                 if (key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
1060                         if (del_nr == 0)
1061                                 continue;
1062                         else
1063                                 break;
1064                 }
1065
1066                 if (del_s == -1)
1067                         del_s = i;
1068                 del_nr++;
1069                 if (key.type == BTRFS_EXTENT_ITEM_KEY ||
1070                     key.type == BTRFS_METADATA_ITEM_KEY) {
1071                         old_val = btrfs_super_bytes_used(fs_info->super_copy);
1072                         if (key.type == BTRFS_METADATA_ITEM_KEY)
1073                                 old_val += root->leafsize;
1074                         else
1075                                 old_val += key.offset;
1076                         btrfs_set_super_bytes_used(fs_info->super_copy,
1077                                                    old_val);
1078                 }
1079         }
1080
1081         if (del_nr) {
1082                 ret = btrfs_del_items(trans, root, &path, del_s, del_nr);
1083                 if (ret)
1084                         goto err;
1085         }
1086
1087         if (key.objectid < end) {
1088                 if (key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
1089                         key.objectid += root->sectorsize;
1090                         key.type = BTRFS_EXTENT_ITEM_KEY;
1091                         key.offset = 0;
1092                 }
1093                 btrfs_release_path(&path);
1094                 goto again;
1095         }
1096 err:
1097         btrfs_release_path(&path);
1098         return ret;
1099 }
1100
1101 static int block_group_free_all_extent(struct btrfs_root *root,
1102                                        struct block_group_record *bg)
1103 {
1104         struct btrfs_block_group_cache *cache;
1105         struct btrfs_fs_info *info;
1106         u64 start;
1107         u64 end;
1108
1109         info = root->fs_info;
1110         cache = btrfs_lookup_block_group(info, bg->objectid);
1111         if (!cache)
1112                 return -ENOENT;
1113
1114         start = cache->key.objectid;
1115         end = start + cache->key.offset - 1;
1116
1117         set_extent_bits(&info->block_group_cache, start, end,
1118                         BLOCK_GROUP_DIRTY, GFP_NOFS);
1119         set_extent_dirty(&info->free_space_cache, start, end, GFP_NOFS);
1120
1121         btrfs_set_block_group_used(&cache->item, 0);
1122
1123         return 0;
1124 }
1125
1126 static int remove_chunk_extent_item(struct btrfs_trans_handle *trans,
1127                                     struct recover_control *rc,
1128                                     struct btrfs_root *root)
1129 {
1130         struct chunk_record *chunk;
1131         int ret = 0;
1132
1133         list_for_each_entry(chunk, &rc->good_chunks, list) {
1134                 if (!(chunk->type_flags & BTRFS_BLOCK_GROUP_SYSTEM))
1135                         continue;
1136                 ret = block_group_remove_all_extent_items(trans, root,
1137                                                           chunk->bg_rec);
1138                 if (ret)
1139                         return ret;
1140
1141                 ret = block_group_free_all_extent(root, chunk->bg_rec);
1142                 if (ret)
1143                         return ret;
1144         }
1145         return ret;
1146 }
1147
1148 static int __rebuild_chunk_root(struct btrfs_trans_handle *trans,
1149                                 struct recover_control *rc,
1150                                 struct btrfs_root *root)
1151 {
1152         u64 min_devid = -1;
1153         struct btrfs_device *dev;
1154         struct extent_buffer *cow;
1155         struct btrfs_disk_key disk_key;
1156         int ret = 0;
1157
1158         list_for_each_entry(dev, &rc->fs_devices->devices, dev_list) {
1159                 if (min_devid > dev->devid)
1160                         min_devid = dev->devid;
1161         }
1162         disk_key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1163         disk_key.type = BTRFS_DEV_ITEM_KEY;
1164         disk_key.offset = min_devid;
1165
1166         cow = btrfs_alloc_free_block(trans, root, root->nodesize,
1167                                      BTRFS_CHUNK_TREE_OBJECTID,
1168                                      &disk_key, 0, 0, 0);
1169         btrfs_set_header_bytenr(cow, cow->start);
1170         btrfs_set_header_generation(cow, trans->transid);
1171         btrfs_set_header_nritems(cow, 0);
1172         btrfs_set_header_level(cow, 0);
1173         btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV);
1174         btrfs_set_header_owner(cow, BTRFS_CHUNK_TREE_OBJECTID);
1175         write_extent_buffer(cow, root->fs_info->fsid,
1176                         btrfs_header_fsid(), BTRFS_FSID_SIZE);
1177
1178         write_extent_buffer(cow, root->fs_info->chunk_tree_uuid,
1179                         btrfs_header_chunk_tree_uuid(cow),
1180                         BTRFS_UUID_SIZE);
1181
1182         root->node = cow;
1183         btrfs_mark_buffer_dirty(cow);
1184
1185         return ret;
1186 }
1187
1188 static int __rebuild_device_items(struct btrfs_trans_handle *trans,
1189                                   struct recover_control *rc,
1190                                   struct btrfs_root *root)
1191 {
1192         struct btrfs_device *dev;
1193         struct btrfs_key key;
1194         struct btrfs_dev_item *dev_item;
1195         int ret = 0;
1196
1197         dev_item = malloc(sizeof(struct btrfs_dev_item));
1198         if (!dev_item)
1199                 return -ENOMEM;
1200
1201         list_for_each_entry(dev, &rc->fs_devices->devices, dev_list) {
1202                 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1203                 key.type = BTRFS_DEV_ITEM_KEY;
1204                 key.offset = dev->devid;
1205
1206                 btrfs_set_stack_device_generation(dev_item, 0);
1207                 btrfs_set_stack_device_type(dev_item, dev->type);
1208                 btrfs_set_stack_device_id(dev_item, dev->devid);
1209                 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
1210                 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
1211                 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
1212                 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
1213                 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
1214                 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
1215                 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
1216
1217                 ret = btrfs_insert_item(trans, root, &key,
1218                                         dev_item, sizeof(*dev_item));
1219         }
1220
1221         free(dev_item);
1222         return ret;
1223 }
1224
1225 static int __insert_chunk_item(struct btrfs_trans_handle *trans,
1226                                 struct chunk_record *chunk_rec,
1227                                 struct btrfs_root *chunk_root)
1228 {
1229         struct btrfs_key key;
1230         struct btrfs_chunk *chunk = NULL;
1231         int ret = 0;
1232
1233         chunk = create_chunk_item(chunk_rec);
1234         if (!chunk)
1235                 return -ENOMEM;
1236         key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
1237         key.type = BTRFS_CHUNK_ITEM_KEY;
1238         key.offset = chunk_rec->offset;
1239
1240         ret = btrfs_insert_item(trans, chunk_root, &key, chunk,
1241                                 btrfs_chunk_item_size(chunk->num_stripes));
1242         free(chunk);
1243         return ret;
1244 }
1245
1246 static int __rebuild_chunk_items(struct btrfs_trans_handle *trans,
1247                                  struct recover_control *rc,
1248                                  struct btrfs_root *root)
1249 {
1250         struct btrfs_root *chunk_root;
1251         struct chunk_record *chunk_rec;
1252         int ret;
1253
1254         chunk_root = root->fs_info->chunk_root;
1255
1256         list_for_each_entry(chunk_rec, &rc->good_chunks, list) {
1257                 ret = __insert_chunk_item(trans, chunk_rec, chunk_root);
1258                 if (ret)
1259                         return ret;
1260         }
1261         list_for_each_entry(chunk_rec, &rc->rebuild_chunks, list) {
1262                 ret = __insert_chunk_item(trans, chunk_rec, chunk_root);
1263                 if (ret)
1264                         return ret;
1265         }
1266         return 0;
1267 }
1268
1269 static int rebuild_chunk_tree(struct btrfs_trans_handle *trans,
1270                               struct recover_control *rc,
1271                               struct btrfs_root *root)
1272 {
1273         int ret = 0;
1274
1275         root = root->fs_info->chunk_root;
1276
1277         ret = __rebuild_chunk_root(trans, rc, root);
1278         if (ret)
1279                 return ret;
1280
1281         ret = __rebuild_device_items(trans, rc, root);
1282         if (ret)
1283                 return ret;
1284
1285         ret = __rebuild_chunk_items(trans, rc, root);
1286
1287         return ret;
1288 }
1289
1290 static int rebuild_sys_array(struct recover_control *rc,
1291                              struct btrfs_root *root)
1292 {
1293         struct btrfs_chunk *chunk;
1294         struct btrfs_key key;
1295         struct chunk_record *chunk_rec;
1296         int ret = 0;
1297         u16 num_stripes;
1298
1299         btrfs_set_super_sys_array_size(root->fs_info->super_copy, 0);
1300
1301         list_for_each_entry(chunk_rec, &rc->good_chunks, list) {
1302                 if (!(chunk_rec->type_flags & BTRFS_BLOCK_GROUP_SYSTEM))
1303                         continue;
1304
1305                 num_stripes = chunk_rec->num_stripes;
1306                 chunk = create_chunk_item(chunk_rec);
1307                 if (!chunk) {
1308                         ret = -ENOMEM;
1309                         break;
1310                 }
1311
1312                 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
1313                 key.type = BTRFS_CHUNK_ITEM_KEY;
1314                 key.offset = chunk_rec->offset;
1315
1316                 ret = btrfs_add_system_chunk(NULL, root, &key, chunk,
1317                                 btrfs_chunk_item_size(num_stripes));
1318                 free(chunk);
1319                 if (ret)
1320                         break;
1321         }
1322         return ret;
1323
1324 }
1325
1326 static int calculate_bg_used(struct btrfs_root *extent_root,
1327                              struct chunk_record *chunk_rec,
1328                              struct btrfs_path *path,
1329                              u64 *used)
1330 {
1331         struct extent_buffer *node;
1332         struct btrfs_key found_key;
1333         int slot;
1334         int ret = 0;
1335         u64 used_ret = 0;
1336
1337         while (1) {
1338                 node = path->nodes[0];
1339                 slot = path->slots[0];
1340                 btrfs_item_key_to_cpu(node, &found_key, slot);
1341                 if (found_key.objectid >= chunk_rec->offset + chunk_rec->length)
1342                         break;
1343                 if (found_key.type != BTRFS_METADATA_ITEM_KEY &&
1344                     found_key.type != BTRFS_EXTENT_DATA_KEY)
1345                         goto next;
1346                 if (found_key.type == BTRFS_METADATA_ITEM_KEY)
1347                         used_ret += extent_root->nodesize;
1348                 else
1349                         used_ret += found_key.offset;
1350 next:
1351                 if (slot + 1 < btrfs_header_nritems(node)) {
1352                         slot++;
1353                 } else {
1354                         ret = btrfs_next_leaf(extent_root, path);
1355                         if (ret > 0) {
1356                                 ret = 0;
1357                                 break;
1358                         }
1359                         if (ret < 0)
1360                                 break;
1361                 }
1362         }
1363         if (!ret)
1364                 *used = used_ret;
1365         return ret;
1366 }
1367
1368 static int __insert_block_group(struct btrfs_trans_handle *trans,
1369                                 struct chunk_record *chunk_rec,
1370                                 struct btrfs_root *extent_root,
1371                                 u64 used)
1372 {
1373         struct btrfs_block_group_item bg_item;
1374         struct btrfs_key key;
1375         int ret = 0;
1376
1377         btrfs_set_block_group_used(&bg_item, used);
1378         btrfs_set_block_group_chunk_objectid(&bg_item, used);
1379         btrfs_set_block_group_flags(&bg_item, chunk_rec->type_flags);
1380         key.objectid = chunk_rec->offset;
1381         key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
1382         key.offset = chunk_rec->length;
1383
1384         ret = btrfs_insert_item(trans, extent_root, &key, &bg_item,
1385                                 sizeof(bg_item));
1386         return ret;
1387 }
1388
1389 /*
1390  * Search through the extent tree to rebuild the 'used' member of the block
1391  * group.
1392  * However, since block group and extent item shares the extent tree,
1393  * the extent item may also missing.
1394  * In that case, we fill the 'used' with the length of the block group to
1395  * ensure no write into the block group.
1396  * Btrfsck will hate it but we will inform user to call '--init-extent-tree'
1397  * if possible, or just salvage as much data as possible from the fs.
1398  */
1399 static int rebuild_block_group(struct btrfs_trans_handle *trans,
1400                                struct recover_control *rc,
1401                                struct btrfs_root *root)
1402 {
1403         struct chunk_record *chunk_rec;
1404         struct btrfs_key search_key;
1405         struct btrfs_path *path;
1406         u64 used = 0;
1407         int ret = 0;
1408
1409         if (list_empty(&rc->rebuild_chunks))
1410                 return 0;
1411
1412         path = btrfs_alloc_path();
1413         if (!path)
1414                 return -ENOMEM;
1415         list_for_each_entry(chunk_rec, &rc->rebuild_chunks, list) {
1416                 search_key.objectid = chunk_rec->offset;
1417                 search_key.type = BTRFS_EXTENT_ITEM_KEY;
1418                 search_key.offset = 0;
1419                 ret = btrfs_search_slot(NULL, root->fs_info->extent_root,
1420                                         &search_key, path, 0, 0);
1421                 if (ret < 0)
1422                         goto out;
1423                 ret = calculate_bg_used(root->fs_info->extent_root,
1424                                         chunk_rec, path, &used);
1425                 /*
1426                  * Extent tree is damaged, better to rebuild the whole extent
1427                  * tree. Currently, change the used to chunk's len to prevent
1428                  * write/block reserve happening in that block group.
1429                  */
1430                 if (ret < 0) {
1431                         fprintf(stderr,
1432                                 "Fail to search extent tree for block group: [%llu,%llu]\n",
1433                                 chunk_rec->offset,
1434                                 chunk_rec->offset + chunk_rec->length);
1435                         fprintf(stderr,
1436                                 "Mark the block group full to prevent block rsv problems\n");
1437                         used = chunk_rec->length;
1438                 }
1439                 btrfs_release_path(path);
1440                 ret = __insert_block_group(trans, chunk_rec,
1441                                            root->fs_info->extent_root,
1442                                            used);
1443                 if (ret < 0)
1444                         goto out;
1445         }
1446 out:
1447         btrfs_free_path(path);
1448         return ret;
1449 }
1450
1451 static struct btrfs_root *
1452 open_ctree_with_broken_chunk(struct recover_control *rc)
1453 {
1454         struct btrfs_fs_info *fs_info;
1455         struct btrfs_super_block *disk_super;
1456         struct extent_buffer *eb;
1457         u32 sectorsize;
1458         u32 nodesize;
1459         u32 leafsize;
1460         u32 stripesize;
1461         int ret;
1462
1463         fs_info = btrfs_new_fs_info(1, BTRFS_SUPER_INFO_OFFSET);
1464         if (!fs_info) {
1465                 fprintf(stderr, "Failed to allocate memory for fs_info\n");
1466                 return ERR_PTR(-ENOMEM);
1467         }
1468         fs_info->is_chunk_recover = 1;
1469
1470         fs_info->fs_devices = rc->fs_devices;
1471         ret = btrfs_open_devices(fs_info->fs_devices, O_RDWR);
1472         if (ret)
1473                 goto out;
1474
1475         disk_super = fs_info->super_copy;
1476         ret = btrfs_read_dev_super(fs_info->fs_devices->latest_bdev,
1477                                    disk_super, fs_info->super_bytenr, 1);
1478         if (ret) {
1479                 fprintf(stderr, "No valid btrfs found\n");
1480                 goto out_devices;
1481         }
1482
1483         memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
1484
1485         ret = btrfs_check_fs_compatibility(disk_super, 1);
1486         if (ret)
1487                 goto out_devices;
1488
1489         nodesize = btrfs_super_nodesize(disk_super);
1490         leafsize = btrfs_super_leafsize(disk_super);
1491         sectorsize = btrfs_super_sectorsize(disk_super);
1492         stripesize = btrfs_super_stripesize(disk_super);
1493
1494         __setup_root(nodesize, leafsize, sectorsize, stripesize,
1495                      fs_info->chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
1496
1497         ret = build_device_maps_by_chunk_records(rc, fs_info->chunk_root);
1498         if (ret)
1499                 goto out_cleanup;
1500
1501         ret = btrfs_setup_all_roots(fs_info, 0, 0);
1502         if (ret)
1503                 goto out_failed;
1504
1505         eb = fs_info->tree_root->node;
1506         read_extent_buffer(eb, fs_info->chunk_tree_uuid,
1507                            btrfs_header_chunk_tree_uuid(eb),
1508                            BTRFS_UUID_SIZE);
1509
1510         return fs_info->fs_root;
1511 out_failed:
1512         btrfs_release_all_roots(fs_info);
1513 out_cleanup:
1514         btrfs_cleanup_all_caches(fs_info);
1515 out_devices:
1516         btrfs_close_devices(fs_info->fs_devices);
1517 out:
1518         btrfs_free_fs_info(fs_info);
1519         return ERR_PTR(ret);
1520 }
1521
1522 static int recover_prepare(struct recover_control *rc, char *path)
1523 {
1524         int ret;
1525         int fd;
1526         struct btrfs_super_block *sb;
1527         struct btrfs_fs_devices *fs_devices;
1528
1529         ret = 0;
1530         fd = open(path, O_RDONLY);
1531         if (fd < 0) {
1532                 fprintf(stderr, "open %s\n error.\n", path);
1533                 return -1;
1534         }
1535
1536         sb = malloc(BTRFS_SUPER_INFO_SIZE);
1537         if (!sb) {
1538                 fprintf(stderr, "allocating memory for sb failed.\n");
1539                 ret = -ENOMEM;
1540                 goto fail_close_fd;
1541         }
1542
1543         ret = btrfs_read_dev_super(fd, sb, BTRFS_SUPER_INFO_OFFSET, 1);
1544         if (ret) {
1545                 fprintf(stderr, "read super block error\n");
1546                 goto fail_free_sb;
1547         }
1548
1549         rc->sectorsize = btrfs_super_sectorsize(sb);
1550         rc->leafsize = btrfs_super_leafsize(sb);
1551         rc->generation = btrfs_super_generation(sb);
1552         rc->chunk_root_generation = btrfs_super_chunk_root_generation(sb);
1553         rc->csum_size = btrfs_super_csum_size(sb);
1554
1555         /* if seed, the result of scanning below will be partial */
1556         if (btrfs_super_flags(sb) & BTRFS_SUPER_FLAG_SEEDING) {
1557                 fprintf(stderr, "this device is seed device\n");
1558                 ret = -1;
1559                 goto fail_free_sb;
1560         }
1561
1562         ret = btrfs_scan_fs_devices(fd, path, &fs_devices, 0, 1, 0);
1563         if (ret)
1564                 goto fail_free_sb;
1565
1566         rc->fs_devices = fs_devices;
1567
1568         if (rc->verbose)
1569                 print_all_devices(&rc->fs_devices->devices);
1570
1571 fail_free_sb:
1572         free(sb);
1573 fail_close_fd:
1574         close(fd);
1575         return ret;
1576 }
1577
1578 static int btrfs_get_device_extents(u64 chunk_object,
1579                                     struct list_head *orphan_devexts,
1580                                     struct list_head *ret_list)
1581 {
1582         struct device_extent_record *devext;
1583         struct device_extent_record *next;
1584         int count = 0;
1585
1586         list_for_each_entry_safe(devext, next, orphan_devexts, chunk_list) {
1587                 if (devext->chunk_offset == chunk_object) {
1588                         list_move_tail(&devext->chunk_list, ret_list);
1589                         count++;
1590                 }
1591         }
1592         return count;
1593 }
1594
1595 static int calc_num_stripes(u64 type)
1596 {
1597         if (type & (BTRFS_BLOCK_GROUP_RAID0 |
1598                     BTRFS_BLOCK_GROUP_RAID10 |
1599                     BTRFS_BLOCK_GROUP_RAID5 |
1600                     BTRFS_BLOCK_GROUP_RAID6))
1601                 return 0;
1602         else if (type & (BTRFS_BLOCK_GROUP_RAID1 |
1603                          BTRFS_BLOCK_GROUP_DUP))
1604                 return 2;
1605         else
1606                 return 1;
1607 }
1608
1609 static inline int calc_sub_nstripes(u64 type)
1610 {
1611         if (type & BTRFS_BLOCK_GROUP_RAID10)
1612                 return 2;
1613         else
1614                 return 1;
1615 }
1616
1617 static int btrfs_verify_device_extents(struct block_group_record *bg,
1618                                        struct list_head *devexts, int ndevexts)
1619 {
1620         struct device_extent_record *devext;
1621         u64 strpie_length;
1622         int expected_num_stripes;
1623
1624         expected_num_stripes = calc_num_stripes(bg->flags);
1625         if (expected_num_stripes && expected_num_stripes != ndevexts)
1626                 return 1;
1627
1628         strpie_length = calc_stripe_length(bg->flags, bg->offset, ndevexts);
1629         list_for_each_entry(devext, devexts, chunk_list) {
1630                 if (devext->length != strpie_length)
1631                         return 1;
1632         }
1633         return 0;
1634 }
1635
1636 static int btrfs_rebuild_unordered_chunk_stripes(struct recover_control *rc,
1637                                                  struct chunk_record *chunk)
1638 {
1639         struct device_extent_record *devext;
1640         struct btrfs_device *device;
1641         int i;
1642
1643         devext = list_first_entry(&chunk->dextents, struct device_extent_record,
1644                                   chunk_list);
1645         for (i = 0; i < chunk->num_stripes; i++) {
1646                 chunk->stripes[i].devid = devext->objectid;
1647                 chunk->stripes[i].offset = devext->offset;
1648                 device = btrfs_find_device_by_devid(rc->fs_devices,
1649                                                     devext->objectid,
1650                                                     0);
1651                 if (!device)
1652                         return -ENOENT;
1653                 BUG_ON(btrfs_find_device_by_devid(rc->fs_devices,
1654                                                   devext->objectid,
1655                                                   1));
1656                 memcpy(chunk->stripes[i].dev_uuid, device->uuid,
1657                        BTRFS_UUID_SIZE);
1658                 devext = list_next_entry(devext, chunk_list);
1659         }
1660         return 0;
1661 }
1662
1663 static int btrfs_calc_stripe_index(struct chunk_record *chunk, u64 logical)
1664 {
1665         u64 offset = logical - chunk->offset;
1666         int stripe_nr;
1667         int nr_data_stripes;
1668         int index;
1669
1670         stripe_nr = offset / chunk->stripe_len;
1671         if (chunk->type_flags & BTRFS_BLOCK_GROUP_RAID0) {
1672                 index = stripe_nr % chunk->num_stripes;
1673         } else if (chunk->type_flags & BTRFS_BLOCK_GROUP_RAID10) {
1674                 index = stripe_nr % (chunk->num_stripes / chunk->sub_stripes);
1675                 index *= chunk->sub_stripes;
1676         } else if (chunk->type_flags & BTRFS_BLOCK_GROUP_RAID5) {
1677                 nr_data_stripes = chunk->num_stripes - 1;
1678                 index = stripe_nr % nr_data_stripes;
1679                 stripe_nr /= nr_data_stripes;
1680                 index = (index + stripe_nr) % chunk->num_stripes;
1681         } else if (chunk->type_flags & BTRFS_BLOCK_GROUP_RAID6) {
1682                 nr_data_stripes = chunk->num_stripes - 2;
1683                 index = stripe_nr % nr_data_stripes;
1684                 stripe_nr /= nr_data_stripes;
1685                 index = (index + stripe_nr) % chunk->num_stripes;
1686         } else {
1687                 return -1;
1688         }
1689         return index;
1690 }
1691
1692 /* calc the logical offset which is the start of the next stripe. */
1693 static inline u64 btrfs_next_stripe_logical_offset(struct chunk_record *chunk,
1694                                                    u64 logical)
1695 {
1696         u64 offset = logical - chunk->offset;
1697
1698         offset /= chunk->stripe_len;
1699         offset *= chunk->stripe_len;
1700         offset += chunk->stripe_len;
1701
1702         return offset + chunk->offset;
1703 }
1704
1705 static int is_extent_record_in_device_extent(struct extent_record *er,
1706                                              struct device_extent_record *dext,
1707                                              int *mirror)
1708 {
1709         int i;
1710
1711         for (i = 0; i < er->nmirrors; i++) {
1712                 if (er->devices[i]->devid == dext->objectid &&
1713                     er->offsets[i] >= dext->offset &&
1714                     er->offsets[i] < dext->offset + dext->length) {
1715                         *mirror = i;
1716                         return 1;
1717                 }
1718         }
1719         return 0;
1720 }
1721
1722 static int
1723 btrfs_rebuild_ordered_meta_chunk_stripes(struct recover_control *rc,
1724                                          struct chunk_record *chunk)
1725 {
1726         u64 start = chunk->offset;
1727         u64 end = chunk->offset + chunk->length;
1728         struct cache_extent *cache;
1729         struct extent_record *er;
1730         struct device_extent_record *devext;
1731         struct device_extent_record *next;
1732         struct btrfs_device *device;
1733         LIST_HEAD(devexts);
1734         int index;
1735         int mirror;
1736         int ret;
1737
1738         cache = lookup_cache_extent(&rc->eb_cache,
1739                                     start, chunk->length);
1740         if (!cache) {
1741                 /* No used space, we can reorder the stripes freely. */
1742                 ret = btrfs_rebuild_unordered_chunk_stripes(rc, chunk);
1743                 return ret;
1744         }
1745
1746         list_splice_init(&chunk->dextents, &devexts);
1747 again:
1748         er = container_of(cache, struct extent_record, cache);
1749         index = btrfs_calc_stripe_index(chunk, er->cache.start);
1750         BUG_ON(index == -1);
1751         if (chunk->stripes[index].devid)
1752                 goto next;
1753         list_for_each_entry_safe(devext, next, &devexts, chunk_list) {
1754                 if (is_extent_record_in_device_extent(er, devext, &mirror)) {
1755                         chunk->stripes[index].devid = devext->objectid;
1756                         chunk->stripes[index].offset = devext->offset;
1757                         memcpy(chunk->stripes[index].dev_uuid,
1758                                er->devices[mirror]->uuid,
1759                                BTRFS_UUID_SIZE);
1760                         index++;
1761                         list_move(&devext->chunk_list, &chunk->dextents);
1762                 }
1763         }
1764 next:
1765         start = btrfs_next_stripe_logical_offset(chunk, er->cache.start);
1766         if (start >= end)
1767                 goto no_extent_record;
1768
1769         cache = lookup_cache_extent(&rc->eb_cache, start, end - start);
1770         if (cache)
1771                 goto again;
1772 no_extent_record:
1773         if (list_empty(&devexts))
1774                 return 0;
1775
1776         if (chunk->type_flags & (BTRFS_BLOCK_GROUP_RAID5 |
1777                                  BTRFS_BLOCK_GROUP_RAID6)) {
1778                 /* Fixme: try to recover the order by the parity block. */
1779                 list_splice_tail(&devexts, &chunk->dextents);
1780                 return -EINVAL;
1781         }
1782
1783         /* There is no data on the lost stripes, we can reorder them freely. */
1784         for (index = 0; index < chunk->num_stripes; index++) {
1785                 if (chunk->stripes[index].devid)
1786                         continue;
1787
1788                 devext = list_first_entry(&devexts,
1789                                           struct device_extent_record,
1790                                            chunk_list);
1791                 list_move(&devext->chunk_list, &chunk->dextents);
1792
1793                 chunk->stripes[index].devid = devext->objectid;
1794                 chunk->stripes[index].offset = devext->offset;
1795                 device = btrfs_find_device_by_devid(rc->fs_devices,
1796                                                     devext->objectid,
1797                                                     0);
1798                 if (!device) {
1799                         list_splice_tail(&devexts, &chunk->dextents);
1800                         return -EINVAL;
1801                 }
1802                 BUG_ON(btrfs_find_device_by_devid(rc->fs_devices,
1803                                                   devext->objectid,
1804                                                   1));
1805                 memcpy(chunk->stripes[index].dev_uuid, device->uuid,
1806                        BTRFS_UUID_SIZE);
1807         }
1808         return 0;
1809 }
1810
1811 #define BTRFS_ORDERED_RAID      (BTRFS_BLOCK_GROUP_RAID0 |      \
1812                                  BTRFS_BLOCK_GROUP_RAID10 |     \
1813                                  BTRFS_BLOCK_GROUP_RAID5 |      \
1814                                  BTRFS_BLOCK_GROUP_RAID6)
1815
1816 static int btrfs_rebuild_chunk_stripes(struct recover_control *rc,
1817                                        struct chunk_record *chunk)
1818 {
1819         int ret;
1820
1821         /*
1822          * All the data in the system metadata chunk will be dropped,
1823          * so we need not guarantee that the data is right or not, that
1824          * is we can reorder the stripes in the system metadata chunk.
1825          */
1826         if ((chunk->type_flags & BTRFS_BLOCK_GROUP_METADATA) &&
1827             (chunk->type_flags & BTRFS_ORDERED_RAID))
1828                 ret =btrfs_rebuild_ordered_meta_chunk_stripes(rc, chunk);
1829         else if ((chunk->type_flags & BTRFS_BLOCK_GROUP_DATA) &&
1830                  (chunk->type_flags & BTRFS_ORDERED_RAID))
1831                 ret = 1;        /* Be handled after the fs is opened. */
1832         else
1833                 ret = btrfs_rebuild_unordered_chunk_stripes(rc, chunk);
1834
1835         return ret;
1836 }
1837
1838 static int next_csum(struct btrfs_root *root,
1839                      struct extent_buffer **leaf,
1840                      struct btrfs_path *path,
1841                      int *slot,
1842                      u64 *csum_offset,
1843                      u32 *tree_csum,
1844                      u64 end,
1845                      struct btrfs_key *key)
1846 {
1847         int ret = 0;
1848         struct btrfs_root *csum_root = root->fs_info->csum_root;
1849         struct btrfs_csum_item *csum_item;
1850         u32 blocksize = root->sectorsize;
1851         u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
1852         int csums_in_item = btrfs_item_size_nr(*leaf, *slot) / csum_size;
1853
1854         if (*csum_offset >= csums_in_item) {
1855                 ++(*slot);
1856                 *csum_offset = 0;
1857                 if (*slot >= btrfs_header_nritems(*leaf)) {
1858                         ret = btrfs_next_leaf(csum_root, path);
1859                         if (ret < 0)
1860                                 return -1;
1861                         else if (ret > 0)
1862                                 return 1;
1863                         *leaf = path->nodes[0];
1864                         *slot = path->slots[0];
1865                 }
1866                 btrfs_item_key_to_cpu(*leaf, key, *slot);
1867         }
1868
1869         if (key->offset + (*csum_offset) * blocksize >= end)
1870                 return 2;
1871         csum_item = btrfs_item_ptr(*leaf, *slot, struct btrfs_csum_item);
1872         csum_item = (struct btrfs_csum_item *)((unsigned char *)csum_item
1873                                              + (*csum_offset) * csum_size);
1874         read_extent_buffer(*leaf, tree_csum,
1875                           (unsigned long)csum_item, csum_size);
1876         return ret;
1877 }
1878
1879 static u64 calc_data_offset(struct btrfs_key *key,
1880                             struct chunk_record *chunk,
1881                             u64 dev_offset,
1882                             u64 csum_offset,
1883                             u32 blocksize)
1884 {
1885         u64 data_offset;
1886         int logical_stripe_nr;
1887         int dev_stripe_nr;
1888         int nr_data_stripes;
1889
1890         data_offset = key->offset + csum_offset * blocksize - chunk->offset;
1891         nr_data_stripes = chunk->num_stripes;
1892
1893         if (chunk->type_flags & BTRFS_BLOCK_GROUP_RAID5)
1894                 nr_data_stripes -= 1;
1895         else if (chunk->type_flags & BTRFS_BLOCK_GROUP_RAID6)
1896                 nr_data_stripes -= 2;
1897
1898         logical_stripe_nr = data_offset / chunk->stripe_len;
1899         dev_stripe_nr = logical_stripe_nr / nr_data_stripes;
1900
1901         data_offset -= logical_stripe_nr * chunk->stripe_len;
1902         data_offset += dev_stripe_nr * chunk->stripe_len;
1903
1904         return dev_offset + data_offset;
1905 }
1906
1907 static int check_one_csum(int fd, u64 start, u32 len, u32 tree_csum)
1908 {
1909         char *data;
1910         int ret = 0;
1911         u32 csum_result = ~(u32)0;
1912
1913         data = malloc(len);
1914         if (!data)
1915                 return -1;
1916         ret = pread64(fd, data, len, start);
1917         if (ret < 0 || ret != len) {
1918                 ret = -1;
1919                 goto out;
1920         }
1921         ret = 0;
1922         csum_result = btrfs_csum_data(NULL, data, csum_result, len);
1923         btrfs_csum_final(csum_result, (char *)&csum_result);
1924         if (csum_result != tree_csum)
1925                 ret = 1;
1926 out:
1927         free(data);
1928         return ret;
1929 }
1930
1931 static u64 item_end_offset(struct btrfs_root *root, struct btrfs_key *key,
1932                            struct extent_buffer *leaf, int slot) {
1933         u32 blocksize = root->sectorsize;
1934         u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
1935
1936         u64 offset = btrfs_item_size_nr(leaf, slot);
1937         offset /= csum_size;
1938         offset *= blocksize;
1939         offset += key->offset;
1940
1941         return offset;
1942 }
1943
1944 static int insert_stripe(struct list_head *devexts,
1945                          struct recover_control *rc,
1946                          struct chunk_record *chunk,
1947                          int index) {
1948         struct device_extent_record *devext;
1949         struct btrfs_device *dev;
1950
1951         devext = list_entry(devexts->next, struct device_extent_record,
1952                             chunk_list);
1953         dev = btrfs_find_device_by_devid(rc->fs_devices, devext->objectid,
1954                                         0);
1955         if (!dev)
1956                 return 1;
1957         BUG_ON(btrfs_find_device_by_devid(rc->fs_devices, devext->objectid,
1958                                         1));
1959
1960         chunk->stripes[index].devid = devext->objectid;
1961         chunk->stripes[index].offset = devext->offset;
1962         memcpy(chunk->stripes[index].dev_uuid, dev->uuid, BTRFS_UUID_SIZE);
1963
1964         list_move(&devext->chunk_list, &chunk->dextents);
1965
1966         return 0;
1967 }
1968
1969 static inline int count_devext_records(struct list_head *record_list)
1970 {
1971         int num_of_records = 0;
1972         struct device_extent_record *devext;
1973
1974         list_for_each_entry(devext, record_list, chunk_list)
1975                 num_of_records++;
1976
1977         return num_of_records;
1978 }
1979
1980 static int fill_chunk_up(struct chunk_record *chunk, struct list_head *devexts,
1981                          struct recover_control *rc)
1982 {
1983         int ret = 0;
1984         int i;
1985
1986         for (i = 0; i < chunk->num_stripes; i++) {
1987                 if (!chunk->stripes[i].devid) {
1988                         ret = insert_stripe(devexts, rc, chunk, i);
1989                         if (ret)
1990                                 break;
1991                 }
1992         }
1993
1994         return ret;
1995 }
1996
1997 #define EQUAL_STRIPE (1 << 0)
1998
1999 static int rebuild_raid_data_chunk_stripes(struct recover_control *rc,
2000                                            struct btrfs_root *root,
2001                                            struct chunk_record *chunk,
2002                                            u8 *flags)
2003 {
2004         int i;
2005         int ret = 0;
2006         int slot;
2007         struct btrfs_path path;
2008         struct btrfs_key prev_key;
2009         struct btrfs_key key;
2010         struct btrfs_root *csum_root;
2011         struct extent_buffer *leaf;
2012         struct device_extent_record *devext;
2013         struct device_extent_record *next;
2014         struct btrfs_device *dev;
2015         u64 start = chunk->offset;
2016         u64 end = start + chunk->stripe_len;
2017         u64 chunk_end = chunk->offset + chunk->length;
2018         u64 csum_offset = 0;
2019         u64 data_offset;
2020         u32 blocksize = root->sectorsize;
2021         u32 tree_csum;
2022         int index = 0;
2023         int num_unordered = 0;
2024         LIST_HEAD(unordered);
2025         LIST_HEAD(candidates);
2026
2027         csum_root = root->fs_info->csum_root;
2028         btrfs_init_path(&path);
2029         list_splice_init(&chunk->dextents, &candidates);
2030 again:
2031         if (list_is_last(candidates.next, &candidates))
2032                 goto out;
2033
2034         key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
2035         key.type = BTRFS_EXTENT_CSUM_KEY;
2036         key.offset = start;
2037
2038         ret = btrfs_search_slot(NULL, csum_root, &key, &path, 0, 0);
2039         if (ret < 0) {
2040                 fprintf(stderr, "Search csum failed(%d)\n", ret);
2041                 goto fail_out;
2042         }
2043         leaf = path.nodes[0];
2044         slot = path.slots[0];
2045         if (ret > 0) {
2046                 if (slot >= btrfs_header_nritems(leaf)) {
2047                         ret = btrfs_next_leaf(csum_root, &path);
2048                         if (ret < 0) {
2049                                 fprintf(stderr,
2050                                         "Walk tree failed(%d)\n", ret);
2051                                 goto fail_out;
2052                         } else if (ret > 0) {
2053                                 slot = btrfs_header_nritems(leaf) - 1;
2054                                 btrfs_item_key_to_cpu(leaf, &key, slot);
2055                                 if (item_end_offset(root, &key, leaf, slot)
2056                                                                 > start) {
2057                                         csum_offset = start - key.offset;
2058                                         csum_offset /= blocksize;
2059                                         goto next_csum;
2060                                 }
2061                                 goto next_stripe;
2062                         }
2063                         leaf = path.nodes[0];
2064                         slot = path.slots[0];
2065                 }
2066                 btrfs_item_key_to_cpu(leaf, &key, slot);
2067                 ret = btrfs_previous_item(csum_root, &path, 0,
2068                                           BTRFS_EXTENT_CSUM_KEY);
2069                 if (ret < 0)
2070                         goto fail_out;
2071                 else if (ret > 0) {
2072                         if (key.offset >= end)
2073                                 goto next_stripe;
2074                         else
2075                                 goto next_csum;
2076                 }
2077                 leaf = path.nodes[0];
2078                 slot = path.slots[0];
2079
2080                 btrfs_item_key_to_cpu(leaf, &prev_key, slot);
2081                 if (item_end_offset(root, &prev_key, leaf, slot) > start) {
2082                         csum_offset = start - prev_key.offset;
2083                         csum_offset /= blocksize;
2084                         btrfs_item_key_to_cpu(leaf, &key, slot);
2085                 } else {
2086                         if (key.offset >= end)
2087                                 goto next_stripe;
2088                 }
2089
2090                 if (key.offset + csum_offset * blocksize > chunk_end)
2091                         goto out;
2092         }
2093 next_csum:
2094         ret = next_csum(root, &leaf, &path, &slot, &csum_offset, &tree_csum,
2095                         end, &key);
2096         if (ret < 0) {
2097                 fprintf(stderr, "Fetch csum failed\n");
2098                 goto fail_out;
2099         } else if (ret == 1) {
2100                 if (!(*flags & EQUAL_STRIPE))
2101                         *flags |= EQUAL_STRIPE;
2102                 goto out;
2103         } else if (ret == 2)
2104                 goto next_stripe;
2105
2106         list_for_each_entry_safe(devext, next, &candidates, chunk_list) {
2107                 data_offset = calc_data_offset(&key, chunk, devext->offset,
2108                                                csum_offset, blocksize);
2109                 dev = btrfs_find_device_by_devid(rc->fs_devices,
2110                                                  devext->objectid, 0);
2111                 if (!dev) {
2112                         ret = 1;
2113                         goto fail_out;
2114                 }
2115                 BUG_ON(btrfs_find_device_by_devid(rc->fs_devices,
2116                                                   devext->objectid, 1));
2117
2118                 ret = check_one_csum(dev->fd, data_offset, blocksize,
2119                                      tree_csum);
2120                 if (ret < 0)
2121                         goto fail_out;
2122                 else if (ret > 0)
2123                         list_move(&devext->chunk_list, &unordered);
2124         }
2125
2126         if (list_empty(&candidates)) {
2127                 num_unordered = count_devext_records(&unordered);
2128                 if (chunk->type_flags & BTRFS_BLOCK_GROUP_RAID6
2129                                         && num_unordered == 2) {
2130                         btrfs_release_path(&path);
2131                         ret = fill_chunk_up(chunk, &unordered, rc);
2132                         return ret;
2133                 }
2134
2135                 goto next_stripe;
2136         }
2137
2138         if (list_is_last(candidates.next, &candidates)) {
2139                 index = btrfs_calc_stripe_index(chunk,
2140                         key.offset + csum_offset * blocksize);
2141                 BUG_ON(index == -1);
2142                 if (chunk->stripes[index].devid)
2143                         goto next_stripe;
2144                 ret = insert_stripe(&candidates, rc, chunk, index);
2145                 if (ret)
2146                         goto fail_out;
2147         } else {
2148                 csum_offset++;
2149                 goto next_csum;
2150         }
2151 next_stripe:
2152         start = btrfs_next_stripe_logical_offset(chunk, start);
2153         end = min(start + chunk->stripe_len, chunk_end);
2154         list_splice_init(&unordered, &candidates);
2155         btrfs_release_path(&path);
2156         csum_offset = 0;
2157         if (end < chunk_end)
2158                 goto again;
2159 out:
2160         ret = 0;
2161         list_splice_init(&candidates, &unordered);
2162         num_unordered = count_devext_records(&unordered);
2163         if (num_unordered == 1) {
2164                 for (i = 0; i < chunk->num_stripes; i++) {
2165                         if (!chunk->stripes[i].devid) {
2166                                 index = i;
2167                                 break;
2168                         }
2169                 }
2170                 ret = insert_stripe(&unordered, rc, chunk, index);
2171                 if (ret)
2172                         goto fail_out;
2173         } else {
2174                 if ((num_unordered == 2 && chunk->type_flags
2175                         & BTRFS_BLOCK_GROUP_RAID5)
2176                  || (num_unordered == 3 && chunk->type_flags
2177                         & BTRFS_BLOCK_GROUP_RAID6)) {
2178                         ret = fill_chunk_up(chunk, &unordered, rc);
2179                 }
2180         }
2181 fail_out:
2182         ret = !!ret || (list_empty(&unordered) ? 0 : 1);
2183         list_splice_init(&candidates, &chunk->dextents);
2184         list_splice_init(&unordered, &chunk->dextents);
2185         btrfs_release_path(&path);
2186
2187         return ret;
2188 }
2189
2190 static int btrfs_rebuild_ordered_data_chunk_stripes(struct recover_control *rc,
2191                                            struct btrfs_root *root)
2192 {
2193         struct chunk_record *chunk;
2194         struct chunk_record *next;
2195         int ret = 0;
2196         int err;
2197         u8 flags;
2198
2199         list_for_each_entry_safe(chunk, next, &rc->unrepaired_chunks, list) {
2200                 if ((chunk->type_flags & BTRFS_BLOCK_GROUP_DATA)
2201                  && (chunk->type_flags & BTRFS_ORDERED_RAID)) {
2202                         flags = 0;
2203                         err = rebuild_raid_data_chunk_stripes(rc, root, chunk,
2204                                                               &flags);
2205                         if (err) {
2206                                 list_move(&chunk->list, &rc->bad_chunks);
2207                                 if (flags & EQUAL_STRIPE)
2208                                         fprintf(stderr,
2209                         "Failure: too many equal stripes in chunk[%llu %llu]\n",
2210                                                 chunk->offset, chunk->length);
2211                                 if (!ret)
2212                                         ret = err;
2213                         } else
2214                                 list_move(&chunk->list, &rc->good_chunks);
2215                 }
2216         }
2217         return ret;
2218 }
2219
2220 static int btrfs_recover_chunks(struct recover_control *rc)
2221 {
2222         struct chunk_record *chunk;
2223         struct block_group_record *bg;
2224         struct block_group_record *next;
2225         LIST_HEAD(new_chunks);
2226         LIST_HEAD(devexts);
2227         int nstripes;
2228         int ret;
2229
2230         /* create the chunk by block group */
2231         list_for_each_entry_safe(bg, next, &rc->bg.block_groups, list) {
2232                 nstripes = btrfs_get_device_extents(bg->objectid,
2233                                                     &rc->devext.no_chunk_orphans,
2234                                                     &devexts);
2235                 chunk = calloc(1, btrfs_chunk_record_size(nstripes));
2236                 if (!chunk)
2237                         return -ENOMEM;
2238                 INIT_LIST_HEAD(&chunk->dextents);
2239                 chunk->bg_rec = bg;
2240                 chunk->cache.start = bg->objectid;
2241                 chunk->cache.size = bg->offset;
2242                 chunk->objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2243                 chunk->type = BTRFS_CHUNK_ITEM_KEY;
2244                 chunk->offset = bg->objectid;
2245                 chunk->generation = bg->generation;
2246                 chunk->length = bg->offset;
2247                 chunk->owner = BTRFS_CHUNK_TREE_OBJECTID;
2248                 chunk->stripe_len = BTRFS_STRIPE_LEN;
2249                 chunk->type_flags = bg->flags;
2250                 chunk->io_width = BTRFS_STRIPE_LEN;
2251                 chunk->io_align = BTRFS_STRIPE_LEN;
2252                 chunk->sector_size = rc->sectorsize;
2253                 chunk->sub_stripes = calc_sub_nstripes(bg->flags);
2254
2255                 ret = insert_cache_extent(&rc->chunk, &chunk->cache);
2256                 BUG_ON(ret);
2257
2258                 list_del_init(&bg->list);
2259                 if (!nstripes) {
2260                         list_add_tail(&chunk->list, &rc->bad_chunks);
2261                         continue;
2262                 }
2263
2264                 list_splice_init(&devexts, &chunk->dextents);
2265
2266                 ret = btrfs_verify_device_extents(bg, &devexts, nstripes);
2267                 if (ret) {
2268                         list_add_tail(&chunk->list, &rc->bad_chunks);
2269                         continue;
2270                 }
2271
2272                 chunk->num_stripes = nstripes;
2273                 ret = btrfs_rebuild_chunk_stripes(rc, chunk);
2274                 if (ret > 0)
2275                         list_add_tail(&chunk->list, &rc->unrepaired_chunks);
2276                 else if (ret < 0)
2277                         list_add_tail(&chunk->list, &rc->bad_chunks);
2278                 else
2279                         list_add_tail(&chunk->list, &rc->good_chunks);
2280         }
2281         /*
2282          * Don't worry about the lost orphan device extents, they don't
2283          * have its chunk and block group, they must be the old ones that
2284          * we have dropped.
2285          */
2286         return 0;
2287 }
2288
2289 static inline int is_chunk_overlap(struct chunk_record *chunk1,
2290                                    struct chunk_record *chunk2)
2291 {
2292         if (chunk1->offset >= chunk2->offset + chunk2->length ||
2293             chunk1->offset + chunk1->length <= chunk2->offset)
2294                 return 0;
2295         return 1;
2296 }
2297
2298 /* Move invalid(overlap with good chunks) rebuild chunks to bad chunk list */
2299 static void validate_rebuild_chunks(struct recover_control *rc)
2300 {
2301         struct chunk_record *good;
2302         struct chunk_record *rebuild;
2303         struct chunk_record *tmp;
2304
2305         list_for_each_entry_safe(rebuild, tmp, &rc->rebuild_chunks, list) {
2306                 list_for_each_entry(good, &rc->good_chunks, list) {
2307                         if (is_chunk_overlap(rebuild, good)) {
2308                                 list_move_tail(&rebuild->list,
2309                                                &rc->bad_chunks);
2310                                 break;
2311                         }
2312                 }
2313         }
2314 }
2315
2316 /*
2317  * Return 0 when successful, < 0 on error and > 0 if aborted by user
2318  */
2319 int btrfs_recover_chunk_tree(char *path, int verbose, int yes)
2320 {
2321         int ret = 0;
2322         struct btrfs_root *root = NULL;
2323         struct btrfs_trans_handle *trans;
2324         struct recover_control rc;
2325
2326         init_recover_control(&rc, verbose, yes);
2327
2328         ret = recover_prepare(&rc, path);
2329         if (ret) {
2330                 fprintf(stderr, "recover prepare error\n");
2331                 return ret;
2332         }
2333
2334         ret = scan_devices(&rc);
2335         if (ret) {
2336                 fprintf(stderr, "scan chunk headers error\n");
2337                 goto fail_rc;
2338         }
2339
2340         if (cache_tree_empty(&rc.chunk) &&
2341             cache_tree_empty(&rc.bg.tree) &&
2342             cache_tree_empty(&rc.devext.tree)) {
2343                 fprintf(stderr, "no recoverable chunk\n");
2344                 goto fail_rc;
2345         }
2346
2347         print_scan_result(&rc);
2348
2349         ret = check_chunks(&rc.chunk, &rc.bg, &rc.devext, &rc.good_chunks,
2350                            &rc.bad_chunks, &rc.rebuild_chunks, 1);
2351         if (ret) {
2352                 if (!list_empty(&rc.bg.block_groups) ||
2353                     !list_empty(&rc.devext.no_chunk_orphans)) {
2354                         ret = btrfs_recover_chunks(&rc);
2355                         if (ret)
2356                                 goto fail_rc;
2357                 }
2358         } else {
2359                 print_check_result(&rc);
2360                 printf("Check chunks successfully with no orphans\n");
2361                 goto fail_rc;
2362         }
2363         validate_rebuild_chunks(&rc);
2364         print_check_result(&rc);
2365
2366         root = open_ctree_with_broken_chunk(&rc);
2367         if (IS_ERR(root)) {
2368                 fprintf(stderr, "open with broken chunk error\n");
2369                 ret = PTR_ERR(root);
2370                 goto fail_rc;
2371         }
2372
2373         ret = check_all_chunks_by_metadata(&rc, root);
2374         if (ret) {
2375                 fprintf(stderr, "The chunks in memory can not match the metadata of the fs. Repair failed.\n");
2376                 goto fail_close_ctree;
2377         }
2378
2379         ret = btrfs_rebuild_ordered_data_chunk_stripes(&rc, root);
2380         if (ret) {
2381                 fprintf(stderr, "Failed to rebuild ordered chunk stripes.\n");
2382                 goto fail_close_ctree;
2383         }
2384
2385         if (!rc.yes) {
2386                 ret = ask_user("We are going to rebuild the chunk tree on disk, it might destroy the old metadata on the disk, Are you sure?");
2387                 if (!ret) {
2388                         ret = 1;
2389                         goto fail_close_ctree;
2390                 }
2391         }
2392
2393         trans = btrfs_start_transaction(root, 1);
2394         ret = remove_chunk_extent_item(trans, &rc, root);
2395         BUG_ON(ret);
2396
2397         ret = rebuild_chunk_tree(trans, &rc, root);
2398         BUG_ON(ret);
2399
2400         ret = rebuild_sys_array(&rc, root);
2401         BUG_ON(ret);
2402
2403         ret = rebuild_block_group(trans, &rc, root);
2404         if (ret) {
2405                 printf("Fail to rebuild block groups.\n");
2406                 printf("Recommend to run 'btrfs check --init-extent-tree <dev>' after recovery\n");
2407         }
2408
2409         btrfs_commit_transaction(trans, root);
2410 fail_close_ctree:
2411         close_ctree(root);
2412 fail_rc:
2413         free_recover_control(&rc);
2414         return ret;
2415 }