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btrfs-progs: convert: move init_btrfs
[btrfs-progs-unstable/devel.git] / disk-io.c
blobca4578f7cf4634dc378ad9997724e677f587013e
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 #include <stdio.h>
20 #include <stdlib.h>
21 #include <sys/types.h>
22 #include <sys/stat.h>
23 #include <fcntl.h>
24 #include <unistd.h>
25 #include <uuid/uuid.h>
26 #include "kerncompat.h"
27 #include "radix-tree.h"
28 #include "ctree.h"
29 #include "disk-io.h"
30 #include "volumes.h"
31 #include "transaction.h"
32 #include "crc32c.h"
33 #include "utils.h"
34 #include "print-tree.h"
35 #include "rbtree-utils.h"
36
37 /* specified errno for check_tree_block */
38 #define BTRFS_BAD_BYTENR (-1)
39 #define BTRFS_BAD_FSID (-2)
40 #define BTRFS_BAD_LEVEL (-3)
41 #define BTRFS_BAD_NRITEMS (-4)
42
43 /* Calculate max possible nritems for a leaf/node */
44 static u32 max_nritems(u8 level, u32 nodesize)
45 {
46
47 if (level == 0)
48 return ((nodesize - sizeof(struct btrfs_header)) /
49 sizeof(struct btrfs_item));
50 return ((nodesize - sizeof(struct btrfs_header)) /
51 sizeof(struct btrfs_key_ptr));
52 }
53
54 static int check_tree_block(struct btrfs_fs_info *fs_info,
55 struct extent_buffer *buf)
56 {
57
58 struct btrfs_fs_devices *fs_devices;
59 u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
60 int ret = BTRFS_BAD_FSID;
61
62 if (buf->start != btrfs_header_bytenr(buf))
63 return BTRFS_BAD_BYTENR;
64 if (btrfs_header_level(buf) >= BTRFS_MAX_LEVEL)
65 return BTRFS_BAD_LEVEL;
66 if (btrfs_header_nritems(buf) > max_nritems(btrfs_header_level(buf),
67 nodesize))
68 return BTRFS_BAD_NRITEMS;
69
70 /* Only leaf can be empty */
71 if (btrfs_header_nritems(buf) == 0 &&
72 btrfs_header_level(buf) != 0)
73 return BTRFS_BAD_NRITEMS;
74
75 fs_devices = fs_info->fs_devices;
76 while (fs_devices) {
77 if (fs_info->ignore_fsid_mismatch ||
78 !memcmp_extent_buffer(buf, fs_devices->fsid,
79 btrfs_header_fsid(),
80 BTRFS_FSID_SIZE)) {
81 ret = 0;
82 break;
83 }
84 fs_devices = fs_devices->seed;
85 }
86 return ret;
87 }
88
89 static void print_tree_block_error(struct btrfs_fs_info *fs_info,
90 struct extent_buffer *eb,
91 int err)
92 {
93 char fs_uuid[BTRFS_UUID_UNPARSED_SIZE] = {'\0'};
94 char found_uuid[BTRFS_UUID_UNPARSED_SIZE] = {'\0'};
95 u8 buf[BTRFS_UUID_SIZE];
96
97 switch (err) {
98 case BTRFS_BAD_FSID:
99 read_extent_buffer(eb, buf, btrfs_header_fsid(),
100 BTRFS_UUID_SIZE);
101 uuid_unparse(buf, found_uuid);
102 uuid_unparse(fs_info->fsid, fs_uuid);
103 fprintf(stderr, "fsid mismatch, want=%s, have=%s\n",
104 fs_uuid, found_uuid);
105 break;
106 case BTRFS_BAD_BYTENR:
107 fprintf(stderr, "bytenr mismatch, want=%llu, have=%llu\n",
108 eb->start, btrfs_header_bytenr(eb));
109 break;
110 case BTRFS_BAD_LEVEL:
111 fprintf(stderr, "bad level, %u > %u\n",
112 btrfs_header_level(eb), BTRFS_MAX_LEVEL);
113 break;
114 case BTRFS_BAD_NRITEMS:
115 fprintf(stderr, "invalid nr_items: %u\n",
116 btrfs_header_nritems(eb));
117 break;
118 }
119 }
120
121 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
122 {
123 return crc32c(seed, data, len);
124 }
125
126 void btrfs_csum_final(u32 crc, char *result)
127 {
128 put_unaligned_le32(~crc, result);
129 }
130
131 static int __csum_tree_block_size(struct extent_buffer *buf, u16 csum_size,
132 int verify, int silent)
133 {
134 char result[BTRFS_CSUM_SIZE];
135 u32 len;
136 u32 crc = ~(u32)0;
137
138 len = buf->len - BTRFS_CSUM_SIZE;
139 crc = crc32c(crc, buf->data + BTRFS_CSUM_SIZE, len);
140 btrfs_csum_final(crc, result);
141
142 if (verify) {
143 if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
144 if (!silent)
145 printk("checksum verify failed on %llu found %08X wanted %08X\n",
146 (unsigned long long)buf->start,
147 *((u32 *)result),
148 *((u32*)(char *)buf->data));
149 return 1;
150 }
151 } else {
152 write_extent_buffer(buf, result, 0, csum_size);
153 }
154 return 0;
155 }
156
157 int csum_tree_block_size(struct extent_buffer *buf, u16 csum_size, int verify)
158 {
159 return __csum_tree_block_size(buf, csum_size, verify, 0);
160 }
161
162 int verify_tree_block_csum_silent(struct extent_buffer *buf, u16 csum_size)
163 {
164 return __csum_tree_block_size(buf, csum_size, 1, 1);
165 }
166
167 static int csum_tree_block_fs_info(struct btrfs_fs_info *fs_info,
168 struct extent_buffer *buf, int verify)
169 {
170 u16 csum_size =
171 btrfs_super_csum_size(fs_info->super_copy);
172 if (verify && fs_info->suppress_check_block_errors)
173 return verify_tree_block_csum_silent(buf, csum_size);
174 return csum_tree_block_size(buf, csum_size, verify);
175 }
176
177 int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
178 int verify)
179 {
180 return csum_tree_block_fs_info(root->fs_info, buf, verify);
181 }
182
183 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
184 u64 bytenr, u32 blocksize)
185 {
186 return find_extent_buffer(&root->fs_info->extent_cache,
187 bytenr, blocksize);
188 }
189
190 struct extent_buffer* btrfs_find_create_tree_block(
191 struct btrfs_fs_info *fs_info, u64 bytenr, u32 blocksize)
192 {
193 return alloc_extent_buffer(&fs_info->extent_cache, bytenr, blocksize);
194 }
195
196 void readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
197 u64 parent_transid)
198 {
199 struct extent_buffer *eb;
200 u64 length;
201 struct btrfs_multi_bio *multi = NULL;
202 struct btrfs_device *device;
203
204 eb = btrfs_find_tree_block(root, bytenr, blocksize);
205 if (!(eb && btrfs_buffer_uptodate(eb, parent_transid)) &&
206 !btrfs_map_block(&root->fs_info->mapping_tree, READ,
207 bytenr, &length, &multi, 0, NULL)) {
208 device = multi->stripes[0].dev;
209 device->total_ios++;
210 blocksize = min(blocksize, (u32)(64 * 1024));
211 readahead(device->fd, multi->stripes[0].physical, blocksize);
212 }
213
214 free_extent_buffer(eb);
215 kfree(multi);
216 }
217
218 static int verify_parent_transid(struct extent_io_tree *io_tree,
219 struct extent_buffer *eb, u64 parent_transid,
220 int ignore)
221 {
222 int ret;
223
224 if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
225 return 0;
226
227 if (extent_buffer_uptodate(eb) &&
228 btrfs_header_generation(eb) == parent_transid) {
229 ret = 0;
230 goto out;
231 }
232 printk("parent transid verify failed on %llu wanted %llu found %llu\n",
233 (unsigned long long)eb->start,
234 (unsigned long long)parent_transid,
235 (unsigned long long)btrfs_header_generation(eb));
236 if (ignore) {
237 eb->flags |= EXTENT_BAD_TRANSID;
238 printk("Ignoring transid failure\n");
239 return 0;
240 }
241
242 ret = 1;
243 out:
244 clear_extent_buffer_uptodate(io_tree, eb);
245 return ret;
246
247 }
248
249
250 int read_whole_eb(struct btrfs_fs_info *info, struct extent_buffer *eb, int mirror)
251 {
252 unsigned long offset = 0;
253 struct btrfs_multi_bio *multi = NULL;
254 struct btrfs_device *device;
255 int ret = 0;
256 u64 read_len;
257 unsigned long bytes_left = eb->len;
258
259 while (bytes_left) {
260 read_len = bytes_left;
261 device = NULL;
262
263 if (!info->on_restoring &&
264 eb->start != BTRFS_SUPER_INFO_OFFSET) {
265 ret = btrfs_map_block(&info->mapping_tree, READ,
266 eb->start + offset, &read_len, &multi,
267 mirror, NULL);
268 if (ret) {
269 printk("Couldn't map the block %Lu\n", eb->start + offset);
270 kfree(multi);
271 return -EIO;
272 }
273 device = multi->stripes[0].dev;
274
275 if (device->fd <= 0) {
276 kfree(multi);
277 return -EIO;
278 }
279
280 eb->fd = device->fd;
281 device->total_ios++;
282 eb->dev_bytenr = multi->stripes[0].physical;
283 kfree(multi);
284 multi = NULL;
285 } else {
286 /* special case for restore metadump */
287 list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
288 if (device->devid == 1)
289 break;
290 }
291
292 eb->fd = device->fd;
293 eb->dev_bytenr = eb->start;
294 device->total_ios++;
295 }
296
297 if (read_len > bytes_left)
298 read_len = bytes_left;
299
300 ret = read_extent_from_disk(eb, offset, read_len);
301 if (ret)
302 return -EIO;
303 offset += read_len;
304 bytes_left -= read_len;
305 }
306 return 0;
307 }
308
309 struct extent_buffer* read_tree_block_fs_info(
310 struct btrfs_fs_info *fs_info, u64 bytenr, u32 blocksize,
311 u64 parent_transid)
312 {
313 int ret;
314 struct extent_buffer *eb;
315 u64 best_transid = 0;
316 int mirror_num = 0;
317 int good_mirror = 0;
318 int num_copies;
319 int ignore = 0;
320
321 eb = btrfs_find_create_tree_block(fs_info, bytenr, blocksize);
322 if (!eb)
323 return ERR_PTR(-ENOMEM);
324
325 if (btrfs_buffer_uptodate(eb, parent_transid))
326 return eb;
327
328 while (1) {
329 ret = read_whole_eb(fs_info, eb, mirror_num);
330 if (ret == 0 && csum_tree_block_fs_info(fs_info, eb, 1) == 0 &&
331 check_tree_block(fs_info, eb) == 0 &&
332 verify_parent_transid(eb->tree, eb, parent_transid, ignore)
333 == 0) {
334 if (eb->flags & EXTENT_BAD_TRANSID &&
335 list_empty(&eb->recow)) {
336 list_add_tail(&eb->recow,
337 &fs_info->recow_ebs);
338 eb->refs++;
339 }
340 btrfs_set_buffer_uptodate(eb);
341 return eb;
342 }
343 if (ignore) {
344 if (check_tree_block(fs_info, eb)) {
345 if (!fs_info->suppress_check_block_errors)
346 print_tree_block_error(fs_info, eb,
347 check_tree_block(fs_info, eb));
348 } else {
349 if (!fs_info->suppress_check_block_errors)
350 fprintf(stderr, "Csum didn't match\n");
351 }
352 ret = -EIO;
353 break;
354 }
355 num_copies = btrfs_num_copies(&fs_info->mapping_tree,
356 eb->start, eb->len);
357 if (num_copies == 1) {
358 ignore = 1;
359 continue;
360 }
361 if (btrfs_header_generation(eb) > best_transid && mirror_num) {
362 best_transid = btrfs_header_generation(eb);
363 good_mirror = mirror_num;
364 }
365 mirror_num++;
366 if (mirror_num > num_copies) {
367 mirror_num = good_mirror;
368 ignore = 1;
369 continue;
370 }
371 }
372 free_extent_buffer(eb);
373 return ERR_PTR(ret);
374 }
375
376 int read_extent_data(struct btrfs_root *root, char *data,
377 u64 logical, u64 *len, int mirror)
378 {
379 u64 offset = 0;
380 struct btrfs_multi_bio *multi = NULL;
381 struct btrfs_fs_info *info = root->fs_info;
382 struct btrfs_device *device;
383 int ret = 0;
384 u64 max_len = *len;
385
386 ret = btrfs_map_block(&info->mapping_tree, READ, logical, len,
387 &multi, mirror, NULL);
388 if (ret) {
389 fprintf(stderr, "Couldn't map the block %llu\n",
390 logical + offset);
391 goto err;
392 }
393 device = multi->stripes[0].dev;
394
395 if (device->fd <= 0)
396 goto err;
397 if (*len > max_len)
398 *len = max_len;
399
400 ret = pread64(device->fd, data, *len, multi->stripes[0].physical);
401 if (ret != *len)
402 ret = -EIO;
403 else
404 ret = 0;
405 err:
406 kfree(multi);
407 return ret;
408 }
409
410 int write_and_map_eb(struct btrfs_trans_handle *trans,
411 struct btrfs_root *root,
412 struct extent_buffer *eb)
413 {
414 int ret;
415 int dev_nr;
416 u64 length;
417 u64 *raid_map = NULL;
418 struct btrfs_multi_bio *multi = NULL;
419
420 dev_nr = 0;
421 length = eb->len;
422 ret = btrfs_map_block(&root->fs_info->mapping_tree, WRITE,
423 eb->start, &length, &multi, 0, &raid_map);
424
425 if (raid_map) {
426 ret = write_raid56_with_parity(root->fs_info, eb, multi,
427 length, raid_map);
428 BUG_ON(ret);
429 } else while (dev_nr < multi->num_stripes) {
430 BUG_ON(ret);
431 eb->fd = multi->stripes[dev_nr].dev->fd;
432 eb->dev_bytenr = multi->stripes[dev_nr].physical;
433 multi->stripes[dev_nr].dev->total_ios++;
434 dev_nr++;
435 ret = write_extent_to_disk(eb);
436 BUG_ON(ret);
437 }
438 kfree(raid_map);
439 kfree(multi);
440 return 0;
441 }
442
443 int write_tree_block(struct btrfs_trans_handle *trans,
444 struct btrfs_root *root,
445 struct extent_buffer *eb)
446 {
447 if (check_tree_block(root->fs_info, eb)) {
448 print_tree_block_error(root->fs_info, eb,
449 check_tree_block(root->fs_info, eb));
450 BUG();
451 }
452
453 if (trans && !btrfs_buffer_uptodate(eb, trans->transid))
454 BUG();
455
456 btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
457 csum_tree_block(root, eb, 0);
458
459 return write_and_map_eb(trans, root, eb);
460 }
461
462 int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
463 u32 stripesize, struct btrfs_root *root,
464 struct btrfs_fs_info *fs_info, u64 objectid)
465 {
466 root->node = NULL;
467 root->commit_root = NULL;
468 root->sectorsize = sectorsize;
469 root->nodesize = nodesize;
470 root->leafsize = leafsize;
471 root->stripesize = stripesize;
472 root->ref_cows = 0;
473 root->track_dirty = 0;
474
475 root->fs_info = fs_info;
476 root->objectid = objectid;
477 root->last_trans = 0;
478 root->highest_inode = 0;
479 root->last_inode_alloc = 0;
480
481 INIT_LIST_HEAD(&root->dirty_list);
482 INIT_LIST_HEAD(&root->orphan_data_extents);
483 memset(&root->root_key, 0, sizeof(root->root_key));
484 memset(&root->root_item, 0, sizeof(root->root_item));
485 root->root_key.objectid = objectid;
486 return 0;
487 }
488
489 static int update_cowonly_root(struct btrfs_trans_handle *trans,
490 struct btrfs_root *root)
491 {
492 int ret;
493 u64 old_root_bytenr;
494 struct btrfs_root *tree_root = root->fs_info->tree_root;
495
496 btrfs_write_dirty_block_groups(trans, root);
497 while(1) {
498 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
499 if (old_root_bytenr == root->node->start)
500 break;
501 btrfs_set_root_bytenr(&root->root_item,
502 root->node->start);
503 btrfs_set_root_generation(&root->root_item,
504 trans->transid);
505 root->root_item.level = btrfs_header_level(root->node);
506 ret = btrfs_update_root(trans, tree_root,
507 &root->root_key,
508 &root->root_item);
509 BUG_ON(ret);
510 btrfs_write_dirty_block_groups(trans, root);
511 }
512 return 0;
513 }
514
515 static int commit_tree_roots(struct btrfs_trans_handle *trans,
516 struct btrfs_fs_info *fs_info)
517 {
518 struct btrfs_root *root;
519 struct list_head *next;
520 struct extent_buffer *eb;
521 int ret;
522
523 if (fs_info->readonly)
524 return 0;
525
526 eb = fs_info->tree_root->node;
527 extent_buffer_get(eb);
528 ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb);
529 free_extent_buffer(eb);
530 if (ret)
531 return ret;
532
533 while(!list_empty(&fs_info->dirty_cowonly_roots)) {
534 next = fs_info->dirty_cowonly_roots.next;
535 list_del_init(next);
536 root = list_entry(next, struct btrfs_root, dirty_list);
537 update_cowonly_root(trans, root);
538 free_extent_buffer(root->commit_root);
539 root->commit_root = NULL;
540 }
541
542 return 0;
543 }
544
545 static int __commit_transaction(struct btrfs_trans_handle *trans,
546 struct btrfs_root *root)
547 {
548 u64 start;
549 u64 end;
550 struct extent_buffer *eb;
551 struct extent_io_tree *tree = &root->fs_info->extent_cache;
552 int ret;
553
554 while(1) {
555 ret = find_first_extent_bit(tree, 0, &start, &end,
556 EXTENT_DIRTY);
557 if (ret)
558 break;
559 while(start <= end) {
560 eb = find_first_extent_buffer(tree, start);
561 BUG_ON(!eb || eb->start != start);
562 ret = write_tree_block(trans, root, eb);
563 BUG_ON(ret);
564 start += eb->len;
565 clear_extent_buffer_dirty(eb);
566 free_extent_buffer(eb);
567 }
568 }
569 return 0;
570 }
571
572 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
573 struct btrfs_root *root)
574 {
575 u64 transid = trans->transid;
576 int ret = 0;
577 struct btrfs_fs_info *fs_info = root->fs_info;
578
579 if (root->commit_root == root->node)
580 goto commit_tree;
581 if (root == root->fs_info->tree_root)
582 goto commit_tree;
583 if (root == root->fs_info->chunk_root)
584 goto commit_tree;
585
586 free_extent_buffer(root->commit_root);
587 root->commit_root = NULL;
588
589 btrfs_set_root_bytenr(&root->root_item, root->node->start);
590 btrfs_set_root_generation(&root->root_item, trans->transid);
591 root->root_item.level = btrfs_header_level(root->node);
592 ret = btrfs_update_root(trans, root->fs_info->tree_root,
593 &root->root_key, &root->root_item);
594 BUG_ON(ret);
595 commit_tree:
596 ret = commit_tree_roots(trans, fs_info);
597 BUG_ON(ret);
598 ret = __commit_transaction(trans, root);
599 BUG_ON(ret);
600 write_ctree_super(trans, root);
601 btrfs_finish_extent_commit(trans, fs_info->extent_root,
602 &fs_info->pinned_extents);
603 btrfs_free_transaction(root, trans);
604 free_extent_buffer(root->commit_root);
605 root->commit_root = NULL;
606 fs_info->running_transaction = NULL;
607 fs_info->last_trans_committed = transid;
608 return 0;
609 }
610
611 static int find_and_setup_root(struct btrfs_root *tree_root,
612 struct btrfs_fs_info *fs_info,
613 u64 objectid, struct btrfs_root *root)
614 {
615 int ret;
616 u32 blocksize;
617 u64 generation;
618
619 __setup_root(tree_root->nodesize, tree_root->leafsize,
620 tree_root->sectorsize, tree_root->stripesize,
621 root, fs_info, objectid);
622 ret = btrfs_find_last_root(tree_root, objectid,
623 &root->root_item, &root->root_key);
624 if (ret)
625 return ret;
626
627 blocksize = root->nodesize;
628 generation = btrfs_root_generation(&root->root_item);
629 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
630 blocksize, generation);
631 if (!extent_buffer_uptodate(root->node))
632 return -EIO;
633
634 return 0;
635 }
636
637 static int find_and_setup_log_root(struct btrfs_root *tree_root,
638 struct btrfs_fs_info *fs_info,
639 struct btrfs_super_block *disk_super)
640 {
641 u32 blocksize;
642 u64 blocknr = btrfs_super_log_root(disk_super);
643 struct btrfs_root *log_root = malloc(sizeof(struct btrfs_root));
644
645 if (!log_root)
646 return -ENOMEM;
647
648 if (blocknr == 0) {
649 free(log_root);
650 return 0;
651 }
652
653 blocksize = tree_root->nodesize;
654
655 __setup_root(tree_root->nodesize, tree_root->leafsize,
656 tree_root->sectorsize, tree_root->stripesize,
657 log_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
658
659 log_root->node = read_tree_block(tree_root, blocknr,
660 blocksize,
661 btrfs_super_generation(disk_super) + 1);
662
663 fs_info->log_root_tree = log_root;
664
665 if (!extent_buffer_uptodate(log_root->node)) {
666 free_extent_buffer(log_root->node);
667 free(log_root);
668 fs_info->log_root_tree = NULL;
669 return -EIO;
670 }
671
672 return 0;
673 }
674
675 int btrfs_free_fs_root(struct btrfs_root *root)
676 {
677 if (root->node)
678 free_extent_buffer(root->node);
679 if (root->commit_root)
680 free_extent_buffer(root->commit_root);
681 kfree(root);
682 return 0;
683 }
684
685 static void __free_fs_root(struct rb_node *node)
686 {
687 struct btrfs_root *root;
688
689 root = container_of(node, struct btrfs_root, rb_node);
690 btrfs_free_fs_root(root);
691 }
692
693 FREE_RB_BASED_TREE(fs_roots, __free_fs_root);
694
695 struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
696 struct btrfs_key *location)
697 {
698 struct btrfs_root *root;
699 struct btrfs_root *tree_root = fs_info->tree_root;
700 struct btrfs_path *path;
701 struct extent_buffer *l;
702 u64 generation;
703 u32 blocksize;
704 int ret = 0;
705
706 root = calloc(1, sizeof(*root));
707 if (!root)
708 return ERR_PTR(-ENOMEM);
709 if (location->offset == (u64)-1) {
710 ret = find_and_setup_root(tree_root, fs_info,
711 location->objectid, root);
712 if (ret) {
713 free(root);
714 return ERR_PTR(ret);
715 }
716 goto insert;
717 }
718
719 __setup_root(tree_root->nodesize, tree_root->leafsize,
720 tree_root->sectorsize, tree_root->stripesize,
721 root, fs_info, location->objectid);
722
723 path = btrfs_alloc_path();
724 BUG_ON(!path);
725 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
726 if (ret != 0) {
727 if (ret > 0)
728 ret = -ENOENT;
729 goto out;
730 }
731 l = path->nodes[0];
732 read_extent_buffer(l, &root->root_item,
733 btrfs_item_ptr_offset(l, path->slots[0]),
734 sizeof(root->root_item));
735 memcpy(&root->root_key, location, sizeof(*location));
736 ret = 0;
737 out:
738 btrfs_free_path(path);
739 if (ret) {
740 free(root);
741 return ERR_PTR(ret);
742 }
743 generation = btrfs_root_generation(&root->root_item);
744 blocksize = root->nodesize;
745 root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
746 blocksize, generation);
747 if (!extent_buffer_uptodate(root->node)) {
748 free(root);
749 return ERR_PTR(-EIO);
750 }
751 insert:
752 root->ref_cows = 1;
753 return root;
754 }
755
756 static int btrfs_fs_roots_compare_objectids(struct rb_node *node,
757 void *data)
758 {
759 u64 objectid = *((u64 *)data);
760 struct btrfs_root *root;
761
762 root = rb_entry(node, struct btrfs_root, rb_node);
763 if (objectid > root->objectid)
764 return 1;
765 else if (objectid < root->objectid)
766 return -1;
767 else
768 return 0;
769 }
770
771 static int btrfs_fs_roots_compare_roots(struct rb_node *node1,
772 struct rb_node *node2)
773 {
774 struct btrfs_root *root;
775
776 root = rb_entry(node2, struct btrfs_root, rb_node);
777 return btrfs_fs_roots_compare_objectids(node1, (void *)&root->objectid);
778 }
779
780 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
781 struct btrfs_key *location)
782 {
783 struct btrfs_root *root;
784 struct rb_node *node;
785 int ret;
786 u64 objectid = location->objectid;
787
788 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
789 return fs_info->tree_root;
790 if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
791 return fs_info->extent_root;
792 if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
793 return fs_info->chunk_root;
794 if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
795 return fs_info->dev_root;
796 if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
797 return fs_info->csum_root;
798 if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
799 return fs_info->quota_root;
800
801 BUG_ON(location->objectid == BTRFS_TREE_RELOC_OBJECTID ||
802 location->offset != (u64)-1);
803
804 node = rb_search(&fs_info->fs_root_tree, (void *)&objectid,
805 btrfs_fs_roots_compare_objectids, NULL);
806 if (node)
807 return container_of(node, struct btrfs_root, rb_node);
808
809 root = btrfs_read_fs_root_no_cache(fs_info, location);
810 if (IS_ERR(root))
811 return root;
812
813 ret = rb_insert(&fs_info->fs_root_tree, &root->rb_node,
814 btrfs_fs_roots_compare_roots);
815 BUG_ON(ret);
816 return root;
817 }
818
819 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
820 {
821 free(fs_info->tree_root);
822 free(fs_info->extent_root);
823 free(fs_info->chunk_root);
824 free(fs_info->dev_root);
825 free(fs_info->csum_root);
826 free(fs_info->quota_root);
827 free(fs_info->free_space_root);
828 free(fs_info->super_copy);
829 free(fs_info->log_root_tree);
830 free(fs_info);
831 }
832
833 struct btrfs_fs_info *btrfs_new_fs_info(int writable, u64 sb_bytenr)
834 {
835 struct btrfs_fs_info *fs_info;
836
837 fs_info = calloc(1, sizeof(struct btrfs_fs_info));
838 if (!fs_info)
839 return NULL;
840
841 fs_info->tree_root = calloc(1, sizeof(struct btrfs_root));
842 fs_info->extent_root = calloc(1, sizeof(struct btrfs_root));
843 fs_info->chunk_root = calloc(1, sizeof(struct btrfs_root));
844 fs_info->dev_root = calloc(1, sizeof(struct btrfs_root));
845 fs_info->csum_root = calloc(1, sizeof(struct btrfs_root));
846 fs_info->quota_root = calloc(1, sizeof(struct btrfs_root));
847 fs_info->free_space_root = calloc(1, sizeof(struct btrfs_root));
848 fs_info->super_copy = calloc(1, BTRFS_SUPER_INFO_SIZE);
849
850 if (!fs_info->tree_root || !fs_info->extent_root ||
851 !fs_info->chunk_root || !fs_info->dev_root ||
852 !fs_info->csum_root || !fs_info->quota_root ||
853 !fs_info->free_space_root || !fs_info->super_copy)
854 goto free_all;
855
856 extent_io_tree_init(&fs_info->extent_cache);
857 extent_io_tree_init(&fs_info->free_space_cache);
858 extent_io_tree_init(&fs_info->block_group_cache);
859 extent_io_tree_init(&fs_info->pinned_extents);
860 extent_io_tree_init(&fs_info->pending_del);
861 extent_io_tree_init(&fs_info->extent_ins);
862 fs_info->excluded_extents = NULL;
863
864 fs_info->fs_root_tree = RB_ROOT;
865 cache_tree_init(&fs_info->mapping_tree.cache_tree);
866
867 mutex_init(&fs_info->fs_mutex);
868 INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
869 INIT_LIST_HEAD(&fs_info->space_info);
870 INIT_LIST_HEAD(&fs_info->recow_ebs);
871
872 if (!writable)
873 fs_info->readonly = 1;
874
875 fs_info->super_bytenr = sb_bytenr;
876 fs_info->data_alloc_profile = (u64)-1;
877 fs_info->metadata_alloc_profile = (u64)-1;
878 fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
879 return fs_info;
880 free_all:
881 btrfs_free_fs_info(fs_info);
882 return NULL;
883 }
884
885 int btrfs_check_fs_compatibility(struct btrfs_super_block *sb, int writable)
886 {
887 u64 features;
888
889 features = btrfs_super_incompat_flags(sb) &
890 ~BTRFS_FEATURE_INCOMPAT_SUPP;
891 if (features) {
892 printk("couldn't open because of unsupported "
893 "option features (%Lx).\n",
894 (unsigned long long)features);
895 return -ENOTSUP;
896 }
897
898 features = btrfs_super_incompat_flags(sb);
899 if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
900 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
901 btrfs_set_super_incompat_flags(sb, features);
902 }
903
904 features = btrfs_super_compat_ro_flags(sb) &
905 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
906 if (writable && features) {
907 printk("couldn't open RDWR because of unsupported "
908 "option features (%Lx).\n",
909 (unsigned long long)features);
910 return -ENOTSUP;
911 }
912 return 0;
913 }
914
915 static int find_best_backup_root(struct btrfs_super_block *super)
916 {
917 struct btrfs_root_backup *backup;
918 u64 orig_gen = btrfs_super_generation(super);
919 u64 gen = 0;
920 int best_index = 0;
921 int i;
922
923 for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
924 backup = super->super_roots + i;
925 if (btrfs_backup_tree_root_gen(backup) != orig_gen &&
926 btrfs_backup_tree_root_gen(backup) > gen) {
927 best_index = i;
928 gen = btrfs_backup_tree_root_gen(backup);
929 }
930 }
931 return best_index;
932 }
933
934 static int setup_root_or_create_block(struct btrfs_fs_info *fs_info,
935 unsigned flags,
936 struct btrfs_root *info_root,
937 u64 objectid, char *str)
938 {
939 struct btrfs_super_block *sb = fs_info->super_copy;
940 struct btrfs_root *root = fs_info->tree_root;
941 u32 nodesize = btrfs_super_nodesize(sb);
942 int ret;
943
944 ret = find_and_setup_root(root, fs_info, objectid, info_root);
945 if (ret) {
946 printk("Couldn't setup %s tree\n", str);
947 if (!(flags & OPEN_CTREE_PARTIAL))
948 return -EIO;
949 /*
950 * Need a blank node here just so we don't screw up in the
951 * million of places that assume a root has a valid ->node
952 */
953 info_root->node =
954 btrfs_find_create_tree_block(fs_info, 0, nodesize);
955 if (!info_root->node)
956 return -ENOMEM;
957 clear_extent_buffer_uptodate(NULL, info_root->node);
958 }
959
960 return 0;
961 }
962
963 int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info, u64 root_tree_bytenr,
964 unsigned flags)
965 {
966 struct btrfs_super_block *sb = fs_info->super_copy;
967 struct btrfs_root *root;
968 struct btrfs_key key;
969 u32 sectorsize;
970 u32 nodesize;
971 u32 leafsize;
972 u32 stripesize;
973 u64 generation;
974 u32 blocksize;
975 int ret;
976
977 nodesize = btrfs_super_nodesize(sb);
978 leafsize = btrfs_super_leafsize(sb);
979 sectorsize = btrfs_super_sectorsize(sb);
980 stripesize = btrfs_super_stripesize(sb);
981
982 root = fs_info->tree_root;
983 __setup_root(nodesize, leafsize, sectorsize, stripesize,
984 root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
985 blocksize = root->nodesize;
986 generation = btrfs_super_generation(sb);
987
988 if (!root_tree_bytenr && !(flags & OPEN_CTREE_BACKUP_ROOT)) {
989 root_tree_bytenr = btrfs_super_root(sb);
990 } else if (flags & OPEN_CTREE_BACKUP_ROOT) {
991 struct btrfs_root_backup *backup;
992 int index = find_best_backup_root(sb);
993 if (index >= BTRFS_NUM_BACKUP_ROOTS) {
994 fprintf(stderr, "Invalid backup root number\n");
995 return -EIO;
996 }
997 backup = fs_info->super_copy->super_roots + index;
998 root_tree_bytenr = btrfs_backup_tree_root(backup);
999 generation = btrfs_backup_tree_root_gen(backup);
1000 }
1001
1002 root->node = read_tree_block(root, root_tree_bytenr, blocksize,
1003 generation);
1004 if (!extent_buffer_uptodate(root->node)) {
1005 fprintf(stderr, "Couldn't read tree root\n");
1006 return -EIO;
1007 }
1008
1009 ret = setup_root_or_create_block(fs_info, flags, fs_info->extent_root,
1010 BTRFS_EXTENT_TREE_OBJECTID, "extent");
1011 if (ret)
1012 return ret;
1013 fs_info->extent_root->track_dirty = 1;
1014
1015 ret = find_and_setup_root(root, fs_info, BTRFS_DEV_TREE_OBJECTID,
1016 fs_info->dev_root);
1017 if (ret) {
1018 printk("Couldn't setup device tree\n");
1019 return -EIO;
1020 }
1021 fs_info->dev_root->track_dirty = 1;
1022
1023 ret = setup_root_or_create_block(fs_info, flags, fs_info->csum_root,
1024 BTRFS_CSUM_TREE_OBJECTID, "csum");
1025 if (ret)
1026 return ret;
1027 fs_info->csum_root->track_dirty = 1;
1028
1029 ret = find_and_setup_root(root, fs_info, BTRFS_QUOTA_TREE_OBJECTID,
1030 fs_info->quota_root);
1031 if (ret == 0)
1032 fs_info->quota_enabled = 1;
1033
1034 if (btrfs_fs_compat_ro(fs_info, BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE)) {
1035 ret = find_and_setup_root(root, fs_info, BTRFS_FREE_SPACE_TREE_OBJECTID,
1036 fs_info->free_space_root);
1037 if (ret) {
1038 printk("Couldn't read free space tree\n");
1039 return -EIO;
1040 }
1041 fs_info->free_space_root->track_dirty = 1;
1042 }
1043
1044 ret = find_and_setup_log_root(root, fs_info, sb);
1045 if (ret) {
1046 printk("Couldn't setup log root tree\n");
1047 if (!(flags & OPEN_CTREE_PARTIAL))
1048 return -EIO;
1049 }
1050
1051 fs_info->generation = generation;
1052 fs_info->last_trans_committed = generation;
1053 if (extent_buffer_uptodate(fs_info->extent_root->node) &&
1054 !(flags & OPEN_CTREE_NO_BLOCK_GROUPS))
1055 btrfs_read_block_groups(fs_info->tree_root);
1056
1057 key.objectid = BTRFS_FS_TREE_OBJECTID;
1058 key.type = BTRFS_ROOT_ITEM_KEY;
1059 key.offset = (u64)-1;
1060 fs_info->fs_root = btrfs_read_fs_root(fs_info, &key);
1061
1062 if (IS_ERR(fs_info->fs_root))
1063 return -EIO;
1064 return 0;
1065 }
1066
1067 void btrfs_release_all_roots(struct btrfs_fs_info *fs_info)
1068 {
1069 if (fs_info->free_space_root)
1070 free_extent_buffer(fs_info->free_space_root->node);
1071 if (fs_info->quota_root)
1072 free_extent_buffer(fs_info->quota_root->node);
1073 if (fs_info->csum_root)
1074 free_extent_buffer(fs_info->csum_root->node);
1075 if (fs_info->dev_root)
1076 free_extent_buffer(fs_info->dev_root->node);
1077 if (fs_info->extent_root)
1078 free_extent_buffer(fs_info->extent_root->node);
1079 if (fs_info->tree_root)
1080 free_extent_buffer(fs_info->tree_root->node);
1081 if (fs_info->log_root_tree)
1082 free_extent_buffer(fs_info->log_root_tree->node);
1083 if (fs_info->chunk_root)
1084 free_extent_buffer(fs_info->chunk_root->node);
1085 }
1086
1087 static void free_map_lookup(struct cache_extent *ce)
1088 {
1089 struct map_lookup *map;
1090
1091 map = container_of(ce, struct map_lookup, ce);
1092 kfree(map);
1093 }
1094
1095 FREE_EXTENT_CACHE_BASED_TREE(mapping_cache, free_map_lookup);
1096
1097 void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info)
1098 {
1099 while (!list_empty(&fs_info->recow_ebs)) {
1100 struct extent_buffer *eb;
1101 eb = list_first_entry(&fs_info->recow_ebs,
1102 struct extent_buffer, recow);
1103 list_del_init(&eb->recow);
1104 free_extent_buffer(eb);
1105 }
1106 free_mapping_cache_tree(&fs_info->mapping_tree.cache_tree);
1107 extent_io_tree_cleanup(&fs_info->extent_cache);
1108 extent_io_tree_cleanup(&fs_info->free_space_cache);
1109 extent_io_tree_cleanup(&fs_info->block_group_cache);
1110 extent_io_tree_cleanup(&fs_info->pinned_extents);
1111 extent_io_tree_cleanup(&fs_info->pending_del);
1112 extent_io_tree_cleanup(&fs_info->extent_ins);
1113 }
1114
1115 int btrfs_scan_fs_devices(int fd, const char *path,
1116 struct btrfs_fs_devices **fs_devices,
1117 u64 sb_bytenr, unsigned sbflags,
1118 int skip_devices)
1119 {
1120 u64 total_devs;
1121 u64 dev_size;
1122 off_t seek_ret;
1123 int ret;
1124 if (!sb_bytenr)
1125 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
1126
1127 seek_ret = lseek(fd, 0, SEEK_END);
1128 if (seek_ret < 0)
1129 return -errno;
1130
1131 dev_size = seek_ret;
1132 lseek(fd, 0, SEEK_SET);
1133 if (sb_bytenr > dev_size) {
1134 fprintf(stderr, "Superblock bytenr is larger than device size\n");
1135 return -EINVAL;
1136 }
1137
1138 ret = btrfs_scan_one_device(fd, path, fs_devices,
1139 &total_devs, sb_bytenr, sbflags);
1140 if (ret) {
1141 fprintf(stderr, "No valid Btrfs found on %s\n", path);
1142 return ret;
1143 }
1144
1145 if (!skip_devices && total_devs != 1) {
1146 ret = btrfs_scan_lblkid();
1147 if (ret)
1148 return ret;
1149 }
1150 return 0;
1151 }
1152
1153 int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info,
1154 u64 chunk_root_bytenr)
1155 {
1156 struct btrfs_super_block *sb = fs_info->super_copy;
1157 u32 sectorsize;
1158 u32 nodesize;
1159 u32 leafsize;
1160 u32 blocksize;
1161 u32 stripesize;
1162 u64 generation;
1163 int ret;
1164
1165 nodesize = btrfs_super_nodesize(sb);
1166 leafsize = btrfs_super_leafsize(sb);
1167 sectorsize = btrfs_super_sectorsize(sb);
1168 stripesize = btrfs_super_stripesize(sb);
1169
1170 __setup_root(nodesize, leafsize, sectorsize, stripesize,
1171 fs_info->chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
1172
1173 ret = btrfs_read_sys_array(fs_info->chunk_root);
1174 if (ret)
1175 return ret;
1176
1177 blocksize = fs_info->chunk_root->nodesize;
1178 generation = btrfs_super_chunk_root_generation(sb);
1179
1180 if (chunk_root_bytenr && !IS_ALIGNED(chunk_root_bytenr,
1181 btrfs_super_sectorsize(sb))) {
1182 warning("chunk_root_bytenr %llu is unaligned to %u, ignore it",
1183 chunk_root_bytenr, btrfs_super_sectorsize(sb));
1184 chunk_root_bytenr = 0;
1185 }
1186
1187 if (!chunk_root_bytenr)
1188 chunk_root_bytenr = btrfs_super_chunk_root(sb);
1189 else
1190 generation = 0;
1191
1192 fs_info->chunk_root->node = read_tree_block(fs_info->chunk_root,
1193 chunk_root_bytenr,
1194 blocksize, generation);
1195 if (!extent_buffer_uptodate(fs_info->chunk_root->node)) {
1196 if (fs_info->ignore_chunk_tree_error) {
1197 warning("cannot read chunk root, continue anyway");
1198 fs_info->chunk_root = NULL;
1199 return 0;
1200 } else {
1201 error("cannot read chunk root");
1202 return -EIO;
1203 }
1204 }
1205
1206 if (!(btrfs_super_flags(sb) & BTRFS_SUPER_FLAG_METADUMP)) {
1207 ret = btrfs_read_chunk_tree(fs_info->chunk_root);
1208 if (ret) {
1209 fprintf(stderr, "Couldn't read chunk tree\n");
1210 return ret;
1211 }
1212 }
1213 return 0;
1214 }
1215
1216 static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
1217 u64 sb_bytenr,
1218 u64 root_tree_bytenr,
1219 u64 chunk_root_bytenr,
1220 unsigned flags)
1221 {
1222 struct btrfs_fs_info *fs_info;
1223 struct btrfs_super_block *disk_super;
1224 struct btrfs_fs_devices *fs_devices = NULL;
1225 struct extent_buffer *eb;
1226 int ret;
1227 int oflags;
1228 unsigned sbflags = SBREAD_DEFAULT;
1229
1230 if (sb_bytenr == 0)
1231 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
1232
1233 /* try to drop all the caches */
1234 if (posix_fadvise(fp, 0, 0, POSIX_FADV_DONTNEED))
1235 fprintf(stderr, "Warning, could not drop caches\n");
1236
1237 fs_info = btrfs_new_fs_info(flags & OPEN_CTREE_WRITES, sb_bytenr);
1238 if (!fs_info) {
1239 fprintf(stderr, "Failed to allocate memory for fs_info\n");
1240 return NULL;
1241 }
1242 if (flags & OPEN_CTREE_RESTORE)
1243 fs_info->on_restoring = 1;
1244 if (flags & OPEN_CTREE_SUPPRESS_CHECK_BLOCK_ERRORS)
1245 fs_info->suppress_check_block_errors = 1;
1246 if (flags & OPEN_CTREE_IGNORE_FSID_MISMATCH)
1247 fs_info->ignore_fsid_mismatch = 1;
1248 if (flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR)
1249 fs_info->ignore_chunk_tree_error = 1;
1250
1251 if ((flags & OPEN_CTREE_RECOVER_SUPER)
1252 && (flags & OPEN_CTREE_FS_PARTIAL)) {
1253 fprintf(stderr,
1254 "cannot open a partially created filesystem for recovery");
1255 goto out;
1256 }
1257
1258 if (flags & OPEN_CTREE_FS_PARTIAL)
1259 sbflags = SBREAD_PARTIAL;
1260
1261 ret = btrfs_scan_fs_devices(fp, path, &fs_devices, sb_bytenr, sbflags,
1262 (flags & OPEN_CTREE_NO_DEVICES));
1263 if (ret)
1264 goto out;
1265
1266 fs_info->fs_devices = fs_devices;
1267 if (flags & OPEN_CTREE_WRITES)
1268 oflags = O_RDWR;
1269 else
1270 oflags = O_RDONLY;
1271
1272 if (flags & OPEN_CTREE_EXCLUSIVE)
1273 oflags |= O_EXCL;
1274
1275 ret = btrfs_open_devices(fs_devices, oflags);
1276 if (ret)
1277 goto out;
1278
1279 disk_super = fs_info->super_copy;
1280 if (flags & OPEN_CTREE_RECOVER_SUPER)
1281 ret = btrfs_read_dev_super(fs_devices->latest_bdev, disk_super,
1282 sb_bytenr, SBREAD_RECOVER);
1283 else
1284 ret = btrfs_read_dev_super(fp, disk_super, sb_bytenr,
1285 sbflags);
1286 if (ret) {
1287 printk("No valid btrfs found\n");
1288 goto out_devices;
1289 }
1290
1291 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID &&
1292 !fs_info->ignore_fsid_mismatch) {
1293 fprintf(stderr, "ERROR: Filesystem UUID change in progress\n");
1294 goto out_devices;
1295 }
1296
1297 memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
1298
1299 ret = btrfs_check_fs_compatibility(fs_info->super_copy,
1300 flags & OPEN_CTREE_WRITES);
1301 if (ret)
1302 goto out_devices;
1303
1304 ret = btrfs_setup_chunk_tree_and_device_map(fs_info, chunk_root_bytenr);
1305 if (ret)
1306 goto out_chunk;
1307
1308 /* Chunk tree root is unable to read, return directly */
1309 if (!fs_info->chunk_root)
1310 return fs_info;
1311
1312 eb = fs_info->chunk_root->node;
1313 read_extent_buffer(eb, fs_info->chunk_tree_uuid,
1314 btrfs_header_chunk_tree_uuid(eb),
1315 BTRFS_UUID_SIZE);
1316
1317 ret = btrfs_setup_all_roots(fs_info, root_tree_bytenr, flags);
1318 if (ret && !(flags & __OPEN_CTREE_RETURN_CHUNK_ROOT) &&
1319 !fs_info->ignore_chunk_tree_error)
1320 goto out_chunk;
1321
1322 return fs_info;
1323
1324 out_chunk:
1325 btrfs_release_all_roots(fs_info);
1326 btrfs_cleanup_all_caches(fs_info);
1327 out_devices:
1328 btrfs_close_devices(fs_devices);
1329 out:
1330 btrfs_free_fs_info(fs_info);
1331 return NULL;
1332 }
1333
1334 struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
1335 u64 sb_bytenr, u64 root_tree_bytenr,
1336 u64 chunk_root_bytenr,
1337 unsigned flags)
1338 {
1339 int fp;
1340 int ret;
1341 struct btrfs_fs_info *info;
1342 int oflags = O_RDWR;
1343 struct stat st;
1344
1345 ret = stat(filename, &st);
1346 if (ret < 0) {
1347 error("cannot stat '%s': %s", filename, strerror(errno));
1348 return NULL;
1349 }
1350 if (!(((st.st_mode & S_IFMT) == S_IFREG) || ((st.st_mode & S_IFMT) == S_IFBLK))) {
1351 error("not a regular file or block device: %s", filename);
1352 return NULL;
1353 }
1354
1355 if (!(flags & OPEN_CTREE_WRITES))
1356 oflags = O_RDONLY;
1357
1358 fp = open(filename, oflags);
1359 if (fp < 0) {
1360 error("cannot open '%s': %s", filename, strerror(errno));
1361 return NULL;
1362 }
1363 info = __open_ctree_fd(fp, filename, sb_bytenr, root_tree_bytenr,
1364 chunk_root_bytenr, flags);
1365 close(fp);
1366 return info;
1367 }
1368
1369 struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr,
1370 unsigned flags)
1371 {
1372 struct btrfs_fs_info *info;
1373
1374 /* This flags may not return fs_info with any valid root */
1375 BUG_ON(flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR);
1376 info = open_ctree_fs_info(filename, sb_bytenr, 0, 0, flags);
1377 if (!info)
1378 return NULL;
1379 if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
1380 return info->chunk_root;
1381 return info->fs_root;
1382 }
1383
1384 struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
1385 unsigned flags)
1386 {
1387 struct btrfs_fs_info *info;
1388
1389 /* This flags may not return fs_info with any valid root */
1390 BUG_ON(flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR);
1391 info = __open_ctree_fd(fp, path, sb_bytenr, 0, 0, flags);
1392 if (!info)
1393 return NULL;
1394 if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
1395 return info->chunk_root;
1396 return info->fs_root;
1397 }
1398
1399 /*
1400 * Check if the super is valid:
1401 * - nodesize/sectorsize - minimum, maximum, alignment
1402 * - tree block starts - alignment
1403 * - number of devices - something sane
1404 * - sys array size - maximum
1405 */
1406 static int check_super(struct btrfs_super_block *sb, unsigned sbflags)
1407 {
1408 char result[BTRFS_CSUM_SIZE];
1409 u32 crc;
1410 u16 csum_type;
1411 int csum_size;
1412
1413 if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
1414 if (btrfs_super_magic(sb) == BTRFS_MAGIC_PARTIAL) {
1415 if (!(sbflags & SBREAD_PARTIAL)) {
1416 error("superblock magic doesn't match");
1417 return -EIO;
1418 }
1419 }
1420 }
1421
1422 csum_type = btrfs_super_csum_type(sb);
1423 if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) {
1424 error("unsupported checksum algorithm %u\n", csum_type);
1425 return -EIO;
1426 }
1427 csum_size = btrfs_csum_sizes[csum_type];
1428
1429 crc = ~(u32)0;
1430 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
1431 BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1432 btrfs_csum_final(crc, result);
1433
1434 if (memcmp(result, sb->csum, csum_size)) {
1435 error("superblock checksum mismatch");
1436 return -EIO;
1437 }
1438 if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
1439 error("tree_root level too big: %d >= %d",
1440 btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
1441 goto error_out;
1442 }
1443 if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
1444 error("chunk_root level too big: %d >= %d",
1445 btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
1446 goto error_out;
1447 }
1448 if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
1449 error("log_root level too big: %d >= %d",
1450 btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
1451 goto error_out;
1452 }
1453
1454 if (!IS_ALIGNED(btrfs_super_root(sb), 4096)) {
1455 error("tree_root block unaligned: %llu", btrfs_super_root(sb));
1456 goto error_out;
1457 }
1458 if (!IS_ALIGNED(btrfs_super_chunk_root(sb), 4096)) {
1459 error("chunk_root block unaligned: %llu",
1460 btrfs_super_chunk_root(sb));
1461 goto error_out;
1462 }
1463 if (!IS_ALIGNED(btrfs_super_log_root(sb), 4096)) {
1464 error("log_root block unaligned: %llu",
1465 btrfs_super_log_root(sb));
1466 goto error_out;
1467 }
1468 if (btrfs_super_nodesize(sb) < 4096) {
1469 error("nodesize too small: %u < 4096",
1470 btrfs_super_nodesize(sb));
1471 goto error_out;
1472 }
1473 if (!IS_ALIGNED(btrfs_super_nodesize(sb), 4096)) {
1474 error("nodesize unaligned: %u", btrfs_super_nodesize(sb));
1475 goto error_out;
1476 }
1477 if (btrfs_super_sectorsize(sb) < 4096) {
1478 error("sectorsize too small: %u < 4096",
1479 btrfs_super_sectorsize(sb));
1480 goto error_out;
1481 }
1482 if (!IS_ALIGNED(btrfs_super_sectorsize(sb), 4096)) {
1483 error("sectorsize unaligned: %u", btrfs_super_sectorsize(sb));
1484 goto error_out;
1485 }
1486 if (btrfs_super_total_bytes(sb) == 0) {
1487 error("invalid total_bytes 0");
1488 goto error_out;
1489 }
1490 if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
1491 error("invalid bytes_used %llu", btrfs_super_bytes_used(sb));
1492 goto error_out;
1493 }
1494 if ((btrfs_super_stripesize(sb) != 4096)
1495 && (btrfs_super_stripesize(sb) != btrfs_super_sectorsize(sb))) {
1496 error("invalid stripesize %u", btrfs_super_stripesize(sb));
1497 goto error_out;
1498 }
1499
1500 if (memcmp(sb->fsid, sb->dev_item.fsid, BTRFS_UUID_SIZE) != 0) {
1501 char fsid[BTRFS_UUID_UNPARSED_SIZE];
1502 char dev_fsid[BTRFS_UUID_UNPARSED_SIZE];
1503
1504 uuid_unparse(sb->fsid, fsid);
1505 uuid_unparse(sb->dev_item.fsid, dev_fsid);
1506 error("dev_item UUID does not match fsid: %s != %s",
1507 dev_fsid, fsid);
1508 goto error_out;
1509 }
1510
1511 /*
1512 * Hint to catch really bogus numbers, bitflips or so
1513 */
1514 if (btrfs_super_num_devices(sb) > (1UL << 31)) {
1515 warning("suspicious number of devices: %llu",
1516 btrfs_super_num_devices(sb));
1517 }
1518
1519 if (btrfs_super_num_devices(sb) == 0) {
1520 error("number of devices is 0");
1521 goto error_out;
1522 }
1523
1524 /*
1525 * Obvious sys_chunk_array corruptions, it must hold at least one key
1526 * and one chunk
1527 */
1528 if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
1529 error("system chunk array too big %u > %u",
1530 btrfs_super_sys_array_size(sb),
1531 BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
1532 goto error_out;
1533 }
1534 if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
1535 + sizeof(struct btrfs_chunk)) {
1536 error("system chunk array too small %u < %lu",
1537 btrfs_super_sys_array_size(sb),
1538 sizeof(struct btrfs_disk_key) +
1539 sizeof(struct btrfs_chunk));
1540 goto error_out;
1541 }
1542
1543 return 0;
1544
1545 error_out:
1546 error("superblock checksum matches but it has invalid members");
1547 return -EIO;
1548 }
1549
1550 int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr,
1551 unsigned sbflags)
1552 {
1553 u8 fsid[BTRFS_FSID_SIZE];
1554 int fsid_is_initialized = 0;
1555 char tmp[BTRFS_SUPER_INFO_SIZE];
1556 struct btrfs_super_block *buf = (struct btrfs_super_block *)tmp;
1557 int i;
1558 int ret;
1559 int max_super = sbflags & SBREAD_RECOVER ? BTRFS_SUPER_MIRROR_MAX : 1;
1560 u64 transid = 0;
1561 u64 bytenr;
1562
1563 if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) {
1564 ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
1565 if (ret < BTRFS_SUPER_INFO_SIZE)
1566 return -1;
1567
1568 if (btrfs_super_bytenr(buf) != sb_bytenr)
1569 return -1;
1570
1571 if (check_super(buf, sbflags))
1572 return -1;
1573 memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE);
1574 return 0;
1575 }
1576
1577 /*
1578 * we would like to check all the supers, but that would make
1579 * a btrfs mount succeed after a mkfs from a different FS.
1580 * So, we need to add a special mount option to scan for
1581 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
1582 */
1583
1584 for (i = 0; i < max_super; i++) {
1585 bytenr = btrfs_sb_offset(i);
1586 ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, bytenr);
1587 if (ret < BTRFS_SUPER_INFO_SIZE)
1588 break;
1589
1590 if (btrfs_super_bytenr(buf) != bytenr )
1591 continue;
1592 /* if magic is NULL, the device was removed */
1593 if (btrfs_super_magic(buf) == 0 && i == 0)
1594 break;
1595 if (check_super(buf, sbflags))
1596 continue;
1597
1598 if (!fsid_is_initialized) {
1599 memcpy(fsid, buf->fsid, sizeof(fsid));
1600 fsid_is_initialized = 1;
1601 } else if (memcmp(fsid, buf->fsid, sizeof(fsid))) {
1602 /*
1603 * the superblocks (the original one and
1604 * its backups) contain data of different
1605 * filesystems -> the super cannot be trusted
1606 */
1607 continue;
1608 }
1609
1610 if (btrfs_super_generation(buf) > transid) {
1611 memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE);
1612 transid = btrfs_super_generation(buf);
1613 }
1614 }
1615
1616 return transid > 0 ? 0 : -1;
1617 }
1618
1619 static int write_dev_supers(struct btrfs_root *root,
1620 struct btrfs_super_block *sb,
1621 struct btrfs_device *device)
1622 {
1623 u64 bytenr;
1624 u32 crc;
1625 int i, ret;
1626
1627 if (root->fs_info->super_bytenr != BTRFS_SUPER_INFO_OFFSET) {
1628 btrfs_set_super_bytenr(sb, root->fs_info->super_bytenr);
1629 crc = ~(u32)0;
1630 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
1631 BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1632 btrfs_csum_final(crc, (char *)&sb->csum[0]);
1633
1634 /*
1635 * super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
1636 * zero filled, we can use it directly
1637 */
1638 ret = pwrite64(device->fd, root->fs_info->super_copy,
1639 BTRFS_SUPER_INFO_SIZE,
1640 root->fs_info->super_bytenr);
1641 if (ret != BTRFS_SUPER_INFO_SIZE)
1642 goto write_err;
1643 return 0;
1644 }
1645
1646 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1647 bytenr = btrfs_sb_offset(i);
1648 if (bytenr + BTRFS_SUPER_INFO_SIZE > device->total_bytes)
1649 break;
1650
1651 btrfs_set_super_bytenr(sb, bytenr);
1652
1653 crc = ~(u32)0;
1654 crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
1655 BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1656 btrfs_csum_final(crc, (char *)&sb->csum[0]);
1657
1658 /*
1659 * super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
1660 * zero filled, we can use it directly
1661 */
1662 ret = pwrite64(device->fd, root->fs_info->super_copy,
1663 BTRFS_SUPER_INFO_SIZE, bytenr);
1664 if (ret != BTRFS_SUPER_INFO_SIZE)
1665 goto write_err;
1666 }
1667
1668 return 0;
1669
1670 write_err:
1671 if (ret > 0)
1672 fprintf(stderr, "WARNING: failed to write all sb data\n");
1673 else
1674 fprintf(stderr, "WARNING: failed to write sb: %s\n",
1675 strerror(errno));
1676 return ret;
1677 }
1678
1679 int write_all_supers(struct btrfs_root *root)
1680 {
1681 struct list_head *cur;
1682 struct list_head *head = &root->fs_info->fs_devices->devices;
1683 struct btrfs_device *dev;
1684 struct btrfs_super_block *sb;
1685 struct btrfs_dev_item *dev_item;
1686 int ret;
1687 u64 flags;
1688
1689 sb = root->fs_info->super_copy;
1690 dev_item = &sb->dev_item;
1691 list_for_each(cur, head) {
1692 dev = list_entry(cur, struct btrfs_device, dev_list);
1693 if (!dev->writeable)
1694 continue;
1695
1696 btrfs_set_stack_device_generation(dev_item, 0);
1697 btrfs_set_stack_device_type(dev_item, dev->type);
1698 btrfs_set_stack_device_id(dev_item, dev->devid);
1699 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
1700 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
1701 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
1702 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
1703 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
1704 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
1705 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
1706
1707 flags = btrfs_super_flags(sb);
1708 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
1709
1710 ret = write_dev_supers(root, sb, dev);
1711 BUG_ON(ret);
1712 }
1713 return 0;
1714 }
1715
1716 int write_ctree_super(struct btrfs_trans_handle *trans,
1717 struct btrfs_root *root)
1718 {
1719 int ret;
1720 struct btrfs_root *tree_root = root->fs_info->tree_root;
1721 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
1722
1723 if (root->fs_info->readonly)
1724 return 0;
1725
1726 btrfs_set_super_generation(root->fs_info->super_copy,
1727 trans->transid);
1728 btrfs_set_super_root(root->fs_info->super_copy,
1729 tree_root->node->start);
1730 btrfs_set_super_root_level(root->fs_info->super_copy,
1731 btrfs_header_level(tree_root->node));
1732 btrfs_set_super_chunk_root(root->fs_info->super_copy,
1733 chunk_root->node->start);
1734 btrfs_set_super_chunk_root_level(root->fs_info->super_copy,
1735 btrfs_header_level(chunk_root->node));
1736 btrfs_set_super_chunk_root_generation(root->fs_info->super_copy,
1737 btrfs_header_generation(chunk_root->node));
1738
1739 ret = write_all_supers(root);
1740 if (ret)
1741 fprintf(stderr, "failed to write new super block err %d\n", ret);
1742 return ret;
1743 }
1744
1745 int close_ctree_fs_info(struct btrfs_fs_info *fs_info)
1746 {
1747 int ret;
1748 struct btrfs_trans_handle *trans;
1749 struct btrfs_root *root = fs_info->tree_root;
1750
1751 if (fs_info->last_trans_committed !=
1752 fs_info->generation) {
1753 BUG_ON(!root);
1754 trans = btrfs_start_transaction(root, 1);
1755 btrfs_commit_transaction(trans, root);
1756 trans = btrfs_start_transaction(root, 1);
1757 ret = commit_tree_roots(trans, fs_info);
1758 BUG_ON(ret);
1759 ret = __commit_transaction(trans, root);
1760 BUG_ON(ret);
1761 write_ctree_super(trans, root);
1762 btrfs_free_transaction(root, trans);
1763 }
1764
1765 if (fs_info->finalize_on_close) {
1766 btrfs_set_super_magic(fs_info->super_copy, BTRFS_MAGIC);
1767 root->fs_info->finalize_on_close = 0;
1768 ret = write_all_supers(root);
1769 if (ret)
1770 fprintf(stderr,
1771 "failed to write new super block err %d\n", ret);
1772 }
1773 btrfs_free_block_groups(fs_info);
1774
1775 free_fs_roots_tree(&fs_info->fs_root_tree);
1776
1777 btrfs_release_all_roots(fs_info);
1778 btrfs_close_devices(fs_info->fs_devices);
1779 btrfs_cleanup_all_caches(fs_info);
1780 btrfs_free_fs_info(fs_info);
1781 return 0;
1782 }
1783
1784 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1785 struct extent_buffer *eb)
1786 {
1787 return clear_extent_buffer_dirty(eb);
1788 }
1789
1790 int wait_on_tree_block_writeback(struct btrfs_root *root,
1791 struct extent_buffer *eb)
1792 {
1793 return 0;
1794 }
1795
1796 void btrfs_mark_buffer_dirty(struct extent_buffer *eb)
1797 {
1798 set_extent_buffer_dirty(eb);
1799 }
1800
1801 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
1802 {
1803 int ret;
1804
1805 ret = extent_buffer_uptodate(buf);
1806 if (!ret)
1807 return ret;
1808
1809 ret = verify_parent_transid(buf->tree, buf, parent_transid, 1);
1810 return !ret;
1811 }
1812
1813 int btrfs_set_buffer_uptodate(struct extent_buffer *eb)
1814 {
1815 return set_extent_buffer_uptodate(eb);
1816 }
(deprecated) Btrfs progs developments and patch integration