Allow extent_buffers to use more ram
[platform/upstream/btrfs-progs.git] / disk-io.c
1 /*
2  * Copyright (C) 2007 Oracle.  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 #define _XOPEN_SOURCE 600
20 #define __USE_XOPEN2K
21 #define _GNU_SOURCE 1
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <sys/types.h>
25 #include <sys/stat.h>
26 #include <fcntl.h>
27 #include <unistd.h>
28 #include "kerncompat.h"
29 #include "radix-tree.h"
30 #include "ctree.h"
31 #include "disk-io.h"
32 #include "volumes.h"
33 #include "transaction.h"
34 #include "crc32c.h"
35 #include "utils.h"
36 #include "print-tree.h"
37
38 static int close_all_devices(struct btrfs_fs_info *fs_info);
39
40 static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf)
41 {
42
43         struct btrfs_fs_devices *fs_devices;
44         int ret = 1;
45
46         if (buf->start != btrfs_header_bytenr(buf)) {
47                 printk("Check tree block failed, want=%Lu, have=%Lu\n",
48                        buf->start, btrfs_header_bytenr(buf));
49                 return ret;
50         }
51
52         fs_devices = root->fs_info->fs_devices;
53         while (fs_devices) {
54                 if (!memcmp_extent_buffer(buf, fs_devices->fsid,
55                                           (unsigned long)btrfs_header_fsid(buf),
56                                           BTRFS_FSID_SIZE)) {
57                         ret = 0;
58                         break;
59                 }
60                 fs_devices = fs_devices->seed;
61         }
62         return ret;
63 }
64
65 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
66 {
67         return crc32c(seed, data, len);
68 }
69
70 void btrfs_csum_final(u32 crc, char *result)
71 {
72         *(__le32 *)result = ~cpu_to_le32(crc);
73 }
74
75 int csum_tree_block_size(struct extent_buffer *buf, u16 csum_size,
76                          int verify)
77 {
78         char *result;
79         u32 len;
80         u32 crc = ~(u32)0;
81
82         result = malloc(csum_size * sizeof(char));
83         if (!result)
84                 return 1;
85
86         len = buf->len - BTRFS_CSUM_SIZE;
87         crc = crc32c(crc, buf->data + BTRFS_CSUM_SIZE, len);
88         btrfs_csum_final(crc, result);
89
90         if (verify) {
91                 if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
92                         printk("checksum verify failed on %llu wanted %X "
93                                "found %X\n", (unsigned long long)buf->start,
94                                *((int *)result), *((char *)buf->data));
95                         free(result);
96                         return 1;
97                 }
98         } else {
99                 write_extent_buffer(buf, result, 0, csum_size);
100         }
101         free(result);
102         return 0;
103 }
104
105 int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
106                     int verify)
107 {
108         u16 csum_size =
109                 btrfs_super_csum_size(&root->fs_info->super_copy);
110         return csum_tree_block_size(buf, csum_size, verify);
111 }
112
113 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
114                                             u64 bytenr, u32 blocksize)
115 {
116         return find_extent_buffer(&root->fs_info->extent_cache,
117                                   bytenr, blocksize);
118 }
119
120 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
121                                                  u64 bytenr, u32 blocksize)
122 {
123         return alloc_extent_buffer(&root->fs_info->extent_cache, bytenr,
124                                    blocksize);
125 }
126
127 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
128                          u64 parent_transid)
129 {
130         int ret;
131         struct extent_buffer *eb;
132         u64 length;
133         struct btrfs_multi_bio *multi = NULL;
134         struct btrfs_device *device;
135
136         eb = btrfs_find_tree_block(root, bytenr, blocksize);
137         if (eb && btrfs_buffer_uptodate(eb, parent_transid)) {
138                 free_extent_buffer(eb);
139                 return 0;
140         }
141
142         length = blocksize;
143         ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
144                               bytenr, &length, &multi, 0);
145         BUG_ON(ret);
146         device = multi->stripes[0].dev;
147         device->total_ios++;
148         blocksize = min(blocksize, (u32)(64 * 1024));
149         readahead(device->fd, multi->stripes[0].physical, blocksize);
150         kfree(multi);
151         return 0;
152 }
153
154 static int verify_parent_transid(struct extent_io_tree *io_tree,
155                                  struct extent_buffer *eb, u64 parent_transid,
156                                  int ignore)
157 {
158         int ret;
159
160         if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
161                 return 0;
162
163         if (extent_buffer_uptodate(eb) &&
164             btrfs_header_generation(eb) == parent_transid) {
165                 ret = 0;
166                 goto out;
167         }
168         printk("parent transid verify failed on %llu wanted %llu found %llu\n",
169                (unsigned long long)eb->start,
170                (unsigned long long)parent_transid,
171                (unsigned long long)btrfs_header_generation(eb));
172         if (ignore) {
173                 printk("Ignoring transid failure\n");
174                 return 0;
175         }
176
177         ret = 1;
178 out:
179         clear_extent_buffer_uptodate(io_tree, eb);
180         return ret;
181
182 }
183
184
185 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
186                                      u32 blocksize, u64 parent_transid)
187 {
188         int ret;
189         struct extent_buffer *eb;
190         u64 length;
191         u64 best_transid = 0;
192         struct btrfs_multi_bio *multi = NULL;
193         struct btrfs_device *device;
194         int mirror_num = 0;
195         int good_mirror = 0;
196         int num_copies;
197         int ignore = 0;
198
199         eb = btrfs_find_create_tree_block(root, bytenr, blocksize);
200         if (!eb)
201                 return NULL;
202
203         if (btrfs_buffer_uptodate(eb, parent_transid))
204                 return eb;
205
206         length = blocksize;
207         while (1) {
208                 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
209                                       eb->start, &length, &multi, mirror_num);
210                 if (ret) {
211                         printk("Couldn't map the block %Lu\n", bytenr);
212                         break;
213                 }
214                 device = multi->stripes[0].dev;
215                 eb->fd = device->fd;
216                 device->total_ios++;
217                 eb->dev_bytenr = multi->stripes[0].physical;
218                 kfree(multi);
219                 ret = read_extent_from_disk(eb);
220
221                 if (ret == 0 && check_tree_block(root, eb) == 0 &&
222                     csum_tree_block(root, eb, 1) == 0 &&
223                     verify_parent_transid(eb->tree, eb, parent_transid, ignore)
224                     == 0) {
225                         btrfs_set_buffer_uptodate(eb);
226                         return eb;
227                 }
228                 if (ignore) {
229                         if (check_tree_block(root, eb))
230                                 printk("read block failed check_tree_block\n");
231                         else
232                                 printk("Csum didn't match\n");
233                         break;
234                 }
235                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
236                                               eb->start, eb->len);
237                 if (num_copies == 1) {
238                         ignore = 1;
239                         continue;
240                 }
241                 if (btrfs_header_generation(eb) > best_transid) {
242                         best_transid = btrfs_header_generation(eb);
243                         good_mirror = mirror_num;
244                 }
245                 mirror_num++;
246                 if (mirror_num > num_copies) {
247                         mirror_num = good_mirror;
248                         ignore = 1;
249                         continue;
250                 }
251         }
252         free_extent_buffer(eb);
253         return NULL;
254 }
255
256 int write_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
257                      struct extent_buffer *eb)
258 {
259         int ret;
260         int dev_nr;
261         u64 length;
262         struct btrfs_multi_bio *multi = NULL;
263
264         if (check_tree_block(root, eb))
265                 BUG();
266         if (!btrfs_buffer_uptodate(eb, trans->transid))
267                 BUG();
268
269         btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
270         csum_tree_block(root, eb, 0);
271
272         dev_nr = 0;
273         length = eb->len;
274         ret = btrfs_map_block(&root->fs_info->mapping_tree, WRITE,
275                               eb->start, &length, &multi, 0);
276
277         while(dev_nr < multi->num_stripes) {
278                 BUG_ON(ret);
279                 eb->fd = multi->stripes[dev_nr].dev->fd;
280                 eb->dev_bytenr = multi->stripes[dev_nr].physical;
281                 multi->stripes[dev_nr].dev->total_ios++;
282                 dev_nr++;
283                 ret = write_extent_to_disk(eb);
284                 BUG_ON(ret);
285         }
286         kfree(multi);
287         return 0;
288 }
289
290 static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
291                         u32 stripesize, struct btrfs_root *root,
292                         struct btrfs_fs_info *fs_info, u64 objectid)
293 {
294         root->node = NULL;
295         root->commit_root = NULL;
296         root->sectorsize = sectorsize;
297         root->nodesize = nodesize;
298         root->leafsize = leafsize;
299         root->stripesize = stripesize;
300         root->ref_cows = 0;
301         root->track_dirty = 0;
302
303         root->fs_info = fs_info;
304         root->objectid = objectid;
305         root->last_trans = 0;
306         root->highest_inode = 0;
307         root->last_inode_alloc = 0;
308
309         INIT_LIST_HEAD(&root->dirty_list);
310         memset(&root->root_key, 0, sizeof(root->root_key));
311         memset(&root->root_item, 0, sizeof(root->root_item));
312         root->root_key.objectid = objectid;
313         return 0;
314 }
315
316 static int update_cowonly_root(struct btrfs_trans_handle *trans,
317                                struct btrfs_root *root)
318 {
319         int ret;
320         u64 old_root_bytenr;
321         struct btrfs_root *tree_root = root->fs_info->tree_root;
322
323         btrfs_write_dirty_block_groups(trans, root);
324         while(1) {
325                 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
326                 if (old_root_bytenr == root->node->start)
327                         break;
328                 btrfs_set_root_bytenr(&root->root_item,
329                                        root->node->start);
330                 btrfs_set_root_generation(&root->root_item,
331                                           trans->transid);
332                 root->root_item.level = btrfs_header_level(root->node);
333                 ret = btrfs_update_root(trans, tree_root,
334                                         &root->root_key,
335                                         &root->root_item);
336                 BUG_ON(ret);
337                 btrfs_write_dirty_block_groups(trans, root);
338         }
339         return 0;
340 }
341
342 static int commit_tree_roots(struct btrfs_trans_handle *trans,
343                              struct btrfs_fs_info *fs_info)
344 {
345         struct btrfs_root *root;
346         struct list_head *next;
347         struct extent_buffer *eb;
348
349         if (fs_info->readonly)
350                 return 0;
351
352         eb = fs_info->tree_root->node;
353         extent_buffer_get(eb);
354         btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb);
355         free_extent_buffer(eb);
356
357         while(!list_empty(&fs_info->dirty_cowonly_roots)) {
358                 next = fs_info->dirty_cowonly_roots.next;
359                 list_del_init(next);
360                 root = list_entry(next, struct btrfs_root, dirty_list);
361                 update_cowonly_root(trans, root);
362         }
363         return 0;
364 }
365
366 static int __commit_transaction(struct btrfs_trans_handle *trans,
367                                 struct btrfs_root *root)
368 {
369         u64 start;
370         u64 end;
371         struct extent_buffer *eb;
372         struct extent_io_tree *tree = &root->fs_info->extent_cache;
373         int ret;
374
375         while(1) {
376                 ret = find_first_extent_bit(tree, 0, &start, &end,
377                                             EXTENT_DIRTY);
378                 if (ret)
379                         break;
380                 while(start <= end) {
381                         eb = find_first_extent_buffer(tree, start);
382                         BUG_ON(!eb || eb->start != start);
383                         ret = write_tree_block(trans, root, eb);
384                         BUG_ON(ret);
385                         start += eb->len;
386                         clear_extent_buffer_dirty(eb);
387                         free_extent_buffer(eb);
388                 }
389         }
390         return 0;
391 }
392
393 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
394                              struct btrfs_root *root)
395 {
396         u64 transid = trans->transid;
397         int ret = 0;
398         struct btrfs_fs_info *fs_info = root->fs_info;
399
400         if (root->commit_root == root->node)
401                 goto commit_tree;
402
403         free_extent_buffer(root->commit_root);
404         root->commit_root = NULL;
405
406         btrfs_set_root_bytenr(&root->root_item, root->node->start);
407         btrfs_set_root_generation(&root->root_item, trans->transid);
408         root->root_item.level = btrfs_header_level(root->node);
409         ret = btrfs_update_root(trans, root->fs_info->tree_root,
410                                 &root->root_key, &root->root_item);
411         BUG_ON(ret);
412 commit_tree:
413         ret = commit_tree_roots(trans, fs_info);
414         BUG_ON(ret);
415         ret = __commit_transaction(trans, root);
416         BUG_ON(ret);
417         write_ctree_super(trans, root);
418         btrfs_finish_extent_commit(trans, fs_info->extent_root,
419                                    &fs_info->pinned_extents);
420         btrfs_free_transaction(root, trans);
421         free_extent_buffer(root->commit_root);
422         root->commit_root = NULL;
423         fs_info->running_transaction = NULL;
424         fs_info->last_trans_committed = transid;
425         return 0;
426 }
427
428 static int find_and_setup_root(struct btrfs_root *tree_root,
429                                struct btrfs_fs_info *fs_info,
430                                u64 objectid, struct btrfs_root *root)
431 {
432         int ret;
433         u32 blocksize;
434         u64 generation;
435
436         __setup_root(tree_root->nodesize, tree_root->leafsize,
437                      tree_root->sectorsize, tree_root->stripesize,
438                      root, fs_info, objectid);
439         ret = btrfs_find_last_root(tree_root, objectid,
440                                    &root->root_item, &root->root_key);
441         BUG_ON(ret);
442
443         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
444         generation = btrfs_root_generation(&root->root_item);
445         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
446                                      blocksize, generation);
447         if (!extent_buffer_uptodate(root->node))
448                 return -EIO;
449
450         return 0;
451 }
452
453 static int find_and_setup_log_root(struct btrfs_root *tree_root,
454                                struct btrfs_fs_info *fs_info,
455                                struct btrfs_super_block *disk_super)
456 {
457         u32 blocksize;
458         u64 blocknr = btrfs_super_log_root(disk_super);
459         struct btrfs_root *log_root = malloc(sizeof(struct btrfs_root));
460
461         if (blocknr == 0)
462                 return 0;
463
464         blocksize = btrfs_level_size(tree_root,
465                              btrfs_super_log_root_level(disk_super));
466
467         __setup_root(tree_root->nodesize, tree_root->leafsize,
468                      tree_root->sectorsize, tree_root->stripesize,
469                      log_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
470
471         log_root->node = read_tree_block(tree_root, blocknr,
472                                      blocksize,
473                                      btrfs_super_generation(disk_super) + 1);
474
475         fs_info->log_root_tree = log_root;
476
477         if (!extent_buffer_uptodate(log_root->node))
478                 return -EIO;
479         return 0;
480 }
481
482
483 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info,
484                        struct btrfs_root *root)
485 {
486         if (root->node)
487                 free_extent_buffer(root->node);
488         if (root->commit_root)
489                 free_extent_buffer(root->commit_root);
490         kfree(root);
491         return 0;
492 }
493
494 static int free_fs_roots(struct btrfs_fs_info *fs_info)
495 {
496         struct cache_extent *cache;
497         struct btrfs_root *root;
498
499         while (1) {
500                 cache = find_first_cache_extent(&fs_info->fs_root_cache, 0);
501                 if (!cache)
502                         break;
503                 root = container_of(cache, struct btrfs_root, cache);
504                 remove_cache_extent(&fs_info->fs_root_cache, cache);
505                 btrfs_free_fs_root(fs_info, root);
506         }
507         return 0;
508 }
509
510 struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
511                                                struct btrfs_key *location)
512 {
513         struct btrfs_root *root;
514         struct btrfs_root *tree_root = fs_info->tree_root;
515         struct btrfs_path *path;
516         struct extent_buffer *l;
517         u64 generation;
518         u32 blocksize;
519         int ret = 0;
520
521         root = malloc(sizeof(*root));
522         if (!root)
523                 return ERR_PTR(-ENOMEM);
524         memset(root, 0, sizeof(*root));
525         if (location->offset == (u64)-1) {
526                 ret = find_and_setup_root(tree_root, fs_info,
527                                           location->objectid, root);
528                 if (ret) {
529                         free(root);
530                         return ERR_PTR(ret);
531                 }
532                 goto insert;
533         }
534
535         __setup_root(tree_root->nodesize, tree_root->leafsize,
536                      tree_root->sectorsize, tree_root->stripesize,
537                      root, fs_info, location->objectid);
538
539         path = btrfs_alloc_path();
540         BUG_ON(!path);
541         ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
542         if (ret != 0) {
543                 if (ret > 0)
544                         ret = -ENOENT;
545                 goto out;
546         }
547         l = path->nodes[0];
548         read_extent_buffer(l, &root->root_item,
549                btrfs_item_ptr_offset(l, path->slots[0]),
550                sizeof(root->root_item));
551         memcpy(&root->root_key, location, sizeof(*location));
552         ret = 0;
553 out:
554         btrfs_release_path(root, path);
555         btrfs_free_path(path);
556         if (ret) {
557                 free(root);
558                 return ERR_PTR(ret);
559         }
560         generation = btrfs_root_generation(&root->root_item);
561         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
562         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
563                                      blocksize, generation);
564         BUG_ON(!root->node);
565 insert:
566         root->ref_cows = 1;
567         return root;
568 }
569
570 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
571                                       struct btrfs_key *location)
572 {
573         struct btrfs_root *root;
574         struct cache_extent *cache;
575         int ret;
576
577         if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
578                 return fs_info->tree_root;
579         if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
580                 return fs_info->extent_root;
581         if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
582                 return fs_info->chunk_root;
583         if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
584                 return fs_info->dev_root;
585         if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
586                 return fs_info->csum_root;
587
588         BUG_ON(location->objectid == BTRFS_TREE_RELOC_OBJECTID ||
589                location->offset != (u64)-1);
590
591         cache = find_cache_extent(&fs_info->fs_root_cache,
592                                   location->objectid, 1);
593         if (cache)
594                 return container_of(cache, struct btrfs_root, cache);
595
596         root = btrfs_read_fs_root_no_cache(fs_info, location);
597         if (IS_ERR(root))
598                 return root;
599
600         root->cache.start = location->objectid;
601         root->cache.size = 1;
602         ret = insert_existing_cache_extent(&fs_info->fs_root_cache,
603                                            &root->cache);
604         BUG_ON(ret);
605         return root;
606 }
607
608 static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
609                                              u64 sb_bytenr,
610                                              u64 root_tree_bytenr, int writes,
611                                              int partial)
612 {
613         u32 sectorsize;
614         u32 nodesize;
615         u32 leafsize;
616         u32 blocksize;
617         u32 stripesize;
618         u64 generation;
619         struct btrfs_key key;
620         struct btrfs_root *tree_root = malloc(sizeof(struct btrfs_root));
621         struct btrfs_root *extent_root = malloc(sizeof(struct btrfs_root));
622         struct btrfs_root *chunk_root = malloc(sizeof(struct btrfs_root));
623         struct btrfs_root *dev_root = malloc(sizeof(struct btrfs_root));
624         struct btrfs_root *csum_root = malloc(sizeof(struct btrfs_root));
625         struct btrfs_fs_info *fs_info = malloc(sizeof(*fs_info));
626         int ret;
627         struct btrfs_super_block *disk_super;
628         struct btrfs_fs_devices *fs_devices = NULL;
629         u64 total_devs;
630         u64 features;
631
632         if (sb_bytenr == 0)
633                 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
634
635         ret = btrfs_scan_one_device(fp, path, &fs_devices,
636                                     &total_devs, sb_bytenr);
637
638         if (ret) {
639                 fprintf(stderr, "No valid Btrfs found on %s\n", path);
640                 goto out;
641         }
642
643         if (total_devs != 1) {
644                 ret = btrfs_scan_for_fsid(fs_devices, total_devs, 1);
645                 if (ret)
646                         goto out;
647         }
648
649         memset(fs_info, 0, sizeof(*fs_info));
650         fs_info->tree_root = tree_root;
651         fs_info->extent_root = extent_root;
652         fs_info->chunk_root = chunk_root;
653         fs_info->dev_root = dev_root;
654         fs_info->csum_root = csum_root;
655
656         if (!writes)
657                 fs_info->readonly = 1;
658
659         extent_io_tree_init(&fs_info->extent_cache);
660         extent_io_tree_init(&fs_info->free_space_cache);
661         extent_io_tree_init(&fs_info->block_group_cache);
662         extent_io_tree_init(&fs_info->pinned_extents);
663         extent_io_tree_init(&fs_info->pending_del);
664         extent_io_tree_init(&fs_info->extent_ins);
665         cache_tree_init(&fs_info->fs_root_cache);
666
667         cache_tree_init(&fs_info->mapping_tree.cache_tree);
668
669         mutex_init(&fs_info->fs_mutex);
670         fs_info->fs_devices = fs_devices;
671         INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
672         INIT_LIST_HEAD(&fs_info->space_info);
673
674         __setup_root(4096, 4096, 4096, 4096, tree_root,
675                      fs_info, BTRFS_ROOT_TREE_OBJECTID);
676
677         if (writes)
678                 ret = btrfs_open_devices(fs_devices, O_RDWR);
679         else
680                 ret = btrfs_open_devices(fs_devices, O_RDONLY);
681         if (ret)
682                 goto out_cleanup;
683
684         fs_info->super_bytenr = sb_bytenr;
685         disk_super = &fs_info->super_copy;
686         ret = btrfs_read_dev_super(fs_devices->latest_bdev,
687                                    disk_super, sb_bytenr);
688         if (ret) {
689                 printk("No valid btrfs found\n");
690                 goto out_devices;
691         }
692
693         memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
694
695
696         features = btrfs_super_incompat_flags(disk_super) &
697                    ~BTRFS_FEATURE_INCOMPAT_SUPP;
698         if (features) {
699                 printk("couldn't open because of unsupported "
700                        "option features (%Lx).\n",
701                        (unsigned long long)features);
702                 goto out_devices;
703         }
704
705         features = btrfs_super_incompat_flags(disk_super);
706         if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
707                 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
708                 btrfs_set_super_incompat_flags(disk_super, features);
709         }
710
711         features = btrfs_super_compat_ro_flags(disk_super) &
712                 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
713         if (writes && features) {
714                 printk("couldn't open RDWR because of unsupported "
715                        "option features (%Lx).\n",
716                        (unsigned long long)features);
717                 goto out_devices;
718         }
719
720         nodesize = btrfs_super_nodesize(disk_super);
721         leafsize = btrfs_super_leafsize(disk_super);
722         sectorsize = btrfs_super_sectorsize(disk_super);
723         stripesize = btrfs_super_stripesize(disk_super);
724         tree_root->nodesize = nodesize;
725         tree_root->leafsize = leafsize;
726         tree_root->sectorsize = sectorsize;
727         tree_root->stripesize = stripesize;
728
729         ret = btrfs_read_sys_array(tree_root);
730         if (ret)
731                 goto out_devices;
732         blocksize = btrfs_level_size(tree_root,
733                                      btrfs_super_chunk_root_level(disk_super));
734         generation = btrfs_super_chunk_root_generation(disk_super);
735
736         __setup_root(nodesize, leafsize, sectorsize, stripesize,
737                      chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
738
739         chunk_root->node = read_tree_block(chunk_root,
740                                            btrfs_super_chunk_root(disk_super),
741                                            blocksize, generation);
742         if (!extent_buffer_uptodate(chunk_root->node)) {
743                 printk("Couldn't read chunk root\n");
744                 goto out_devices;
745         }
746
747         read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
748                  (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
749                  BTRFS_UUID_SIZE);
750
751         if (!(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_METADUMP)) {
752                 ret = btrfs_read_chunk_tree(chunk_root);
753                 if (ret)
754                         goto out_failed;
755         }
756
757         blocksize = btrfs_level_size(tree_root,
758                                      btrfs_super_root_level(disk_super));
759         generation = btrfs_super_generation(disk_super);
760
761         if (!root_tree_bytenr)
762                 root_tree_bytenr = btrfs_super_root(disk_super);
763         tree_root->node = read_tree_block(tree_root,
764                                           root_tree_bytenr,
765                                           blocksize, generation);
766         if (!extent_buffer_uptodate(tree_root->node)) {
767                 printk("Couldn't read tree root\n");
768                 goto out_failed;
769         }
770         ret = find_and_setup_root(tree_root, fs_info,
771                                   BTRFS_EXTENT_TREE_OBJECTID, extent_root);
772         if (ret) {
773                 printk("Couldn't setup extent tree\n");
774                 goto out_failed;
775         }
776         extent_root->track_dirty = 1;
777
778         ret = find_and_setup_root(tree_root, fs_info,
779                                   BTRFS_DEV_TREE_OBJECTID, dev_root);
780         if (ret) {
781                 printk("Couldn't setup device tree\n");
782                 goto out_failed;
783         }
784         dev_root->track_dirty = 1;
785
786         ret = find_and_setup_root(tree_root, fs_info,
787                                   BTRFS_CSUM_TREE_OBJECTID, csum_root);
788         if (ret) {
789                 printk("Couldn't setup csum tree\n");
790                 goto out_failed;
791         }
792         csum_root->track_dirty = 1;
793
794         find_and_setup_log_root(tree_root, fs_info, disk_super);
795
796         fs_info->generation = generation;
797         fs_info->last_trans_committed = generation;
798         btrfs_read_block_groups(fs_info->tree_root);
799
800         key.objectid = BTRFS_FS_TREE_OBJECTID;
801         key.type = BTRFS_ROOT_ITEM_KEY;
802         key.offset = (u64)-1;
803         fs_info->fs_root = btrfs_read_fs_root(fs_info, &key);
804
805         if (!fs_info->fs_root)
806                 goto out_failed;
807
808         fs_info->data_alloc_profile = (u64)-1;
809         fs_info->metadata_alloc_profile = (u64)-1;
810         fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
811
812         return fs_info;
813
814 out_failed:
815         if (partial)
816                 return fs_info;
817
818         if (fs_info->csum_root)
819                 free_extent_buffer(fs_info->csum_root->node);
820         if (fs_info->dev_root)
821                 free_extent_buffer(fs_info->dev_root->node);
822         if (fs_info->extent_root)
823                 free_extent_buffer(fs_info->extent_root->node);
824         if (fs_info->tree_root)
825                 free_extent_buffer(fs_info->tree_root->node);
826         if (fs_info->chunk_root)
827                 free_extent_buffer(fs_info->chunk_root->node);
828 out_devices:
829         close_all_devices(fs_info);
830 out_cleanup:
831         extent_io_tree_cleanup(&fs_info->extent_cache);
832         extent_io_tree_cleanup(&fs_info->free_space_cache);
833         extent_io_tree_cleanup(&fs_info->block_group_cache);
834         extent_io_tree_cleanup(&fs_info->pinned_extents);
835         extent_io_tree_cleanup(&fs_info->pending_del);
836         extent_io_tree_cleanup(&fs_info->extent_ins);
837 out:
838         free(tree_root);
839         free(extent_root);
840         free(chunk_root);
841         free(dev_root);
842         free(csum_root);
843         free(fs_info);
844         return NULL;
845 }
846
847 struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
848                                          u64 sb_bytenr, int writes,
849                                          int partial)
850 {
851         int fp;
852         struct btrfs_fs_info *info;
853         int flags = O_CREAT | O_RDWR;
854
855         if (!writes)
856                 flags = O_RDONLY;
857
858         fp = open(filename, flags, 0600);
859         if (fp < 0) {
860                 fprintf (stderr, "Could not open %s\n", filename);
861                 return NULL;
862         }
863         info = __open_ctree_fd(fp, filename, sb_bytenr, 0, writes, partial);
864         close(fp);
865         return info;
866 }
867
868 struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr, int writes)
869 {
870         struct btrfs_fs_info *info;
871
872         info = open_ctree_fs_info(filename, sb_bytenr, writes, 0);
873         if (!info)
874                 return NULL;
875         return info->fs_root;
876 }
877
878 struct btrfs_root *open_ctree_recovery(const char *filename, u64 sb_bytenr,
879                                        u64 root_tree_bytenr)
880 {
881         int fp;
882         struct btrfs_fs_info *info;
883
884
885         fp = open(filename, O_RDONLY);
886         if (fp < 0) {
887                 fprintf (stderr, "Could not open %s\n", filename);
888                 return NULL;
889         }
890         info = __open_ctree_fd(fp, filename, sb_bytenr,
891                                root_tree_bytenr, 0, 0);
892         close(fp);
893
894         if (!info)
895                 return NULL;
896         return info->fs_root;
897 }
898
899 struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
900                                  int writes)
901 {
902         struct btrfs_fs_info *info;
903         info = __open_ctree_fd(fp, path, sb_bytenr, 0, writes, 0);
904         if (!info)
905                 return NULL;
906         return info->fs_root;
907 }
908
909 int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr)
910 {
911         u8 fsid[BTRFS_FSID_SIZE];
912         struct btrfs_super_block buf;
913         int i;
914         int ret;
915         u64 transid = 0;
916         u64 bytenr;
917
918         if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) {
919                 ret = pread64(fd, &buf, sizeof(buf), sb_bytenr);
920                 if (ret < sizeof(buf))
921                         return -1;
922
923                 if (btrfs_super_bytenr(&buf) != sb_bytenr ||
924                     strncmp((char *)(&buf.magic), BTRFS_MAGIC,
925                             sizeof(buf.magic)))
926                         return -1;
927
928                 memcpy(sb, &buf, sizeof(*sb));
929                 return 0;
930         }
931
932         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
933                 bytenr = btrfs_sb_offset(i);
934                 ret = pread64(fd, &buf, sizeof(buf), bytenr);
935                 if (ret < sizeof(buf))
936                         break;
937
938                 if (btrfs_super_bytenr(&buf) != bytenr ||
939                     strncmp((char *)(&buf.magic), BTRFS_MAGIC,
940                             sizeof(buf.magic)))
941                         continue;
942
943                 if (i == 0)
944                         memcpy(fsid, buf.fsid, sizeof(fsid));
945                 else if (memcmp(fsid, buf.fsid, sizeof(fsid)))
946                         continue;
947
948                 if (btrfs_super_generation(&buf) > transid) {
949                         memcpy(sb, &buf, sizeof(*sb));
950                         transid = btrfs_super_generation(&buf);
951                 }
952         }
953
954         return transid > 0 ? 0 : -1;
955 }
956
957 int write_dev_supers(struct btrfs_root *root, struct btrfs_super_block *sb,
958                      struct btrfs_device *device)
959 {
960         u64 bytenr;
961         u32 crc;
962         int i, ret;
963
964         if (root->fs_info->super_bytenr != BTRFS_SUPER_INFO_OFFSET) {
965                 btrfs_set_super_bytenr(sb, root->fs_info->super_bytenr);
966                 crc = ~(u32)0;
967                 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
968                                       BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
969                 btrfs_csum_final(crc, (char *)&sb->csum[0]);
970
971                 ret = pwrite64(device->fd, sb, BTRFS_SUPER_INFO_SIZE,
972                                root->fs_info->super_bytenr);
973                 BUG_ON(ret != BTRFS_SUPER_INFO_SIZE);
974                 return 0;
975         }
976
977         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
978                 bytenr = btrfs_sb_offset(i);
979                 if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
980                         break;
981
982                 btrfs_set_super_bytenr(sb, bytenr);
983
984                 crc = ~(u32)0;
985                 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
986                                       BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
987                 btrfs_csum_final(crc, (char *)&sb->csum[0]);
988
989                 ret = pwrite64(device->fd, sb, BTRFS_SUPER_INFO_SIZE, bytenr);
990                 BUG_ON(ret != BTRFS_SUPER_INFO_SIZE);
991         }
992         return 0;
993 }
994
995 int write_all_supers(struct btrfs_root *root)
996 {
997         struct list_head *cur;
998         struct list_head *head = &root->fs_info->fs_devices->devices;
999         struct btrfs_device *dev;
1000         struct btrfs_super_block *sb;
1001         struct btrfs_dev_item *dev_item;
1002         int ret;
1003         u64 flags;
1004
1005         sb = &root->fs_info->super_copy;
1006         dev_item = &sb->dev_item;
1007         list_for_each(cur, head) {
1008                 dev = list_entry(cur, struct btrfs_device, dev_list);
1009                 if (!dev->writeable)
1010                         continue;
1011
1012                 btrfs_set_stack_device_generation(dev_item, 0);
1013                 btrfs_set_stack_device_type(dev_item, dev->type);
1014                 btrfs_set_stack_device_id(dev_item, dev->devid);
1015                 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
1016                 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
1017                 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
1018                 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
1019                 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
1020                 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
1021                 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
1022
1023                 flags = btrfs_super_flags(sb);
1024                 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
1025
1026                 ret = write_dev_supers(root, sb, dev);
1027                 BUG_ON(ret);
1028         }
1029         return 0;
1030 }
1031
1032 int write_ctree_super(struct btrfs_trans_handle *trans,
1033                       struct btrfs_root *root)
1034 {
1035         int ret;
1036         struct btrfs_root *tree_root = root->fs_info->tree_root;
1037         struct btrfs_root *chunk_root = root->fs_info->chunk_root;
1038
1039         if (root->fs_info->readonly)
1040                 return 0;
1041
1042         btrfs_set_super_generation(&root->fs_info->super_copy,
1043                                    trans->transid);
1044         btrfs_set_super_root(&root->fs_info->super_copy,
1045                              tree_root->node->start);
1046         btrfs_set_super_root_level(&root->fs_info->super_copy,
1047                                    btrfs_header_level(tree_root->node));
1048         btrfs_set_super_chunk_root(&root->fs_info->super_copy,
1049                                    chunk_root->node->start);
1050         btrfs_set_super_chunk_root_level(&root->fs_info->super_copy,
1051                                          btrfs_header_level(chunk_root->node));
1052         btrfs_set_super_chunk_root_generation(&root->fs_info->super_copy,
1053                                 btrfs_header_generation(chunk_root->node));
1054
1055         ret = write_all_supers(root);
1056         if (ret)
1057                 fprintf(stderr, "failed to write new super block err %d\n", ret);
1058         return ret;
1059 }
1060
1061 static int close_all_devices(struct btrfs_fs_info *fs_info)
1062 {
1063         struct list_head *list;
1064         struct list_head *next;
1065         struct btrfs_device *device;
1066
1067         return 0;
1068
1069         list = &fs_info->fs_devices->devices;
1070         list_for_each(next, list) {
1071                 device = list_entry(next, struct btrfs_device, dev_list);
1072                 close(device->fd);
1073         }
1074         return 0;
1075 }
1076
1077 int close_ctree(struct btrfs_root *root)
1078 {
1079         int ret;
1080         struct btrfs_trans_handle *trans;
1081         struct btrfs_fs_info *fs_info = root->fs_info;
1082
1083         if (fs_info->last_trans_committed !=
1084             fs_info->generation) {
1085                 trans = btrfs_start_transaction(root, 1);
1086                 btrfs_commit_transaction(trans, root);
1087                 trans = btrfs_start_transaction(root, 1);
1088                 ret = commit_tree_roots(trans, fs_info);
1089                 BUG_ON(ret);
1090                 ret = __commit_transaction(trans, root);
1091                 BUG_ON(ret);
1092                 write_ctree_super(trans, root);
1093                 btrfs_free_transaction(root, trans);
1094         }
1095         btrfs_free_block_groups(fs_info);
1096
1097         free_fs_roots(fs_info);
1098
1099         if (fs_info->extent_root->node)
1100                 free_extent_buffer(fs_info->extent_root->node);
1101         if (fs_info->tree_root->node)
1102                 free_extent_buffer(fs_info->tree_root->node);
1103         if (fs_info->chunk_root->node)
1104                 free_extent_buffer(fs_info->chunk_root->node);
1105         if (fs_info->dev_root->node)
1106                 free_extent_buffer(fs_info->dev_root->node);
1107         if (fs_info->csum_root->node)
1108                 free_extent_buffer(fs_info->csum_root->node);
1109
1110         if (fs_info->log_root_tree) {
1111                 if (fs_info->log_root_tree->node)
1112                         free_extent_buffer(fs_info->log_root_tree->node);
1113                 free(fs_info->log_root_tree);
1114         }
1115
1116         close_all_devices(fs_info);
1117         extent_io_tree_cleanup(&fs_info->extent_cache);
1118         extent_io_tree_cleanup(&fs_info->free_space_cache);
1119         extent_io_tree_cleanup(&fs_info->block_group_cache);
1120         extent_io_tree_cleanup(&fs_info->pinned_extents);
1121         extent_io_tree_cleanup(&fs_info->pending_del);
1122         extent_io_tree_cleanup(&fs_info->extent_ins);
1123
1124         free(fs_info->tree_root);
1125         free(fs_info->extent_root);
1126         free(fs_info->chunk_root);
1127         free(fs_info->dev_root);
1128         free(fs_info->csum_root);
1129         free(fs_info);
1130
1131         return 0;
1132 }
1133
1134 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1135                      struct extent_buffer *eb)
1136 {
1137         return clear_extent_buffer_dirty(eb);
1138 }
1139
1140 int wait_on_tree_block_writeback(struct btrfs_root *root,
1141                                  struct extent_buffer *eb)
1142 {
1143         return 0;
1144 }
1145
1146 void btrfs_mark_buffer_dirty(struct extent_buffer *eb)
1147 {
1148         set_extent_buffer_dirty(eb);
1149 }
1150
1151 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
1152 {
1153         int ret;
1154
1155         ret = extent_buffer_uptodate(buf);
1156         if (!ret)
1157                 return ret;
1158
1159         ret = verify_parent_transid(buf->tree, buf, parent_transid, 1);
1160         return !ret;
1161 }
1162
1163 int btrfs_set_buffer_uptodate(struct extent_buffer *eb)
1164 {
1165         return set_extent_buffer_uptodate(eb);
1166 }