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btrfs-progs: btrfs-progs: Fix read beyond boundary bug in build_roots_info_cache()
[btrfs-progs-unstable/devel.git] / disk-io.c
blob76958aef239e511c21e072c757c0f5e2e23aea59
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 = fs_info->nodesize;
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(char *data, u32 seed, size_t len)
122 {
123 return crc32c(seed, data, len);
124 }
125
126 void btrfs_csum_final(u32 crc, u8 *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 u8 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 int csum_tree_block(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 struct extent_buffer *btrfs_find_tree_block(struct btrfs_fs_info *fs_info,
178 u64 bytenr, u32 blocksize)
179 {
180 return find_extent_buffer(&fs_info->extent_cache,
181 bytenr, blocksize);
182 }
183
184 struct extent_buffer* btrfs_find_create_tree_block(
185 struct btrfs_fs_info *fs_info, u64 bytenr)
186 {
187 return alloc_extent_buffer(&fs_info->extent_cache, bytenr,
188 fs_info->nodesize);
189 }
190
191 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
192 u64 parent_transid)
193 {
194 struct extent_buffer *eb;
195 u64 length;
196 struct btrfs_multi_bio *multi = NULL;
197 struct btrfs_device *device;
198
199 eb = btrfs_find_tree_block(fs_info, bytenr, fs_info->nodesize);
200 if (!(eb && btrfs_buffer_uptodate(eb, parent_transid)) &&
201 !btrfs_map_block(fs_info, READ, bytenr, &length, &multi, 0,
202 NULL)) {
203 device = multi->stripes[0].dev;
204 device->total_ios++;
205 readahead(device->fd, multi->stripes[0].physical,
206 fs_info->nodesize);
207 }
208
209 free_extent_buffer(eb);
210 kfree(multi);
211 }
212
213 static int verify_parent_transid(struct extent_io_tree *io_tree,
214 struct extent_buffer *eb, u64 parent_transid,
215 int ignore)
216 {
217 int ret;
218
219 if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
220 return 0;
221
222 if (extent_buffer_uptodate(eb) &&
223 btrfs_header_generation(eb) == parent_transid) {
224 ret = 0;
225 goto out;
226 }
227 printk("parent transid verify failed on %llu wanted %llu found %llu\n",
228 (unsigned long long)eb->start,
229 (unsigned long long)parent_transid,
230 (unsigned long long)btrfs_header_generation(eb));
231 if (ignore) {
232 eb->flags |= EXTENT_BAD_TRANSID;
233 printk("Ignoring transid failure\n");
234 return 0;
235 }
236
237 ret = 1;
238 out:
239 clear_extent_buffer_uptodate(eb);
240 return ret;
241
242 }
243
244
245 int read_whole_eb(struct btrfs_fs_info *info, struct extent_buffer *eb, int mirror)
246 {
247 unsigned long offset = 0;
248 struct btrfs_multi_bio *multi = NULL;
249 struct btrfs_device *device;
250 int ret = 0;
251 u64 read_len;
252 unsigned long bytes_left = eb->len;
253
254 while (bytes_left) {
255 read_len = bytes_left;
256 device = NULL;
257
258 if (!info->on_restoring &&
259 eb->start != BTRFS_SUPER_INFO_OFFSET) {
260 ret = btrfs_map_block(info, READ, eb->start + offset,
261 &read_len, &multi, mirror, NULL);
262 if (ret) {
263 printk("Couldn't map the block %Lu\n", eb->start + offset);
264 kfree(multi);
265 return -EIO;
266 }
267 device = multi->stripes[0].dev;
268
269 if (device->fd <= 0) {
270 kfree(multi);
271 return -EIO;
272 }
273
274 eb->fd = device->fd;
275 device->total_ios++;
276 eb->dev_bytenr = multi->stripes[0].physical;
277 kfree(multi);
278 multi = NULL;
279 } else {
280 /* special case for restore metadump */
281 list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
282 if (device->devid == 1)
283 break;
284 }
285
286 eb->fd = device->fd;
287 eb->dev_bytenr = eb->start;
288 device->total_ios++;
289 }
290
291 if (read_len > bytes_left)
292 read_len = bytes_left;
293
294 ret = read_extent_from_disk(eb, offset, read_len);
295 if (ret)
296 return -EIO;
297 offset += read_len;
298 bytes_left -= read_len;
299 }
300 return 0;
301 }
302
303 struct extent_buffer* read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
304 u64 parent_transid)
305 {
306 int ret;
307 struct extent_buffer *eb;
308 u64 best_transid = 0;
309 u32 sectorsize = fs_info->sectorsize;
310 int mirror_num = 0;
311 int good_mirror = 0;
312 int num_copies;
313 int ignore = 0;
314
315 /*
316 * Don't even try to create tree block for unaligned tree block
317 * bytenr.
318 * Such unaligned tree block will free overlapping extent buffer,
319 * causing use-after-free bugs for fuzzed images.
320 */
321 if (bytenr < sectorsize || !IS_ALIGNED(bytenr, sectorsize)) {
322 error("tree block bytenr %llu is not aligned to sectorsize %u",
323 bytenr, sectorsize);
324 return ERR_PTR(-EIO);
325 }
326
327 eb = btrfs_find_create_tree_block(fs_info, bytenr);
328 if (!eb)
329 return ERR_PTR(-ENOMEM);
330
331 if (btrfs_buffer_uptodate(eb, parent_transid))
332 return eb;
333
334 while (1) {
335 ret = read_whole_eb(fs_info, eb, mirror_num);
336 if (ret == 0 && csum_tree_block(fs_info, eb, 1) == 0 &&
337 check_tree_block(fs_info, eb) == 0 &&
338 verify_parent_transid(eb->tree, eb, parent_transid, ignore)
339 == 0) {
340 if (eb->flags & EXTENT_BAD_TRANSID &&
341 list_empty(&eb->recow)) {
342 list_add_tail(&eb->recow,
343 &fs_info->recow_ebs);
344 eb->refs++;
345 }
346 btrfs_set_buffer_uptodate(eb);
347 return eb;
348 }
349 if (ignore) {
350 if (check_tree_block(fs_info, eb)) {
351 if (!fs_info->suppress_check_block_errors)
352 print_tree_block_error(fs_info, eb,
353 check_tree_block(fs_info, eb));
354 } else {
355 if (!fs_info->suppress_check_block_errors)
356 fprintf(stderr, "Csum didn't match\n");
357 }
358 ret = -EIO;
359 break;
360 }
361 num_copies = btrfs_num_copies(fs_info, eb->start, eb->len);
362 if (num_copies == 1) {
363 ignore = 1;
364 continue;
365 }
366 if (btrfs_header_generation(eb) > best_transid && mirror_num) {
367 best_transid = btrfs_header_generation(eb);
368 good_mirror = mirror_num;
369 }
370 mirror_num++;
371 if (mirror_num > num_copies) {
372 mirror_num = good_mirror;
373 ignore = 1;
374 continue;
375 }
376 }
377 free_extent_buffer(eb);
378 return ERR_PTR(ret);
379 }
380
381 int read_extent_data(struct btrfs_fs_info *fs_info, char *data, u64 logical,
382 u64 *len, int mirror)
383 {
384 u64 offset = 0;
385 struct btrfs_multi_bio *multi = NULL;
386 struct btrfs_device *device;
387 int ret = 0;
388 u64 max_len = *len;
389
390 ret = btrfs_map_block(fs_info, READ, logical, len, &multi, mirror,
391 NULL);
392 if (ret) {
393 fprintf(stderr, "Couldn't map the block %llu\n",
394 logical + offset);
395 goto err;
396 }
397 device = multi->stripes[0].dev;
398
399 if (device->fd <= 0)
400 goto err;
401 if (*len > max_len)
402 *len = max_len;
403
404 ret = pread64(device->fd, data, *len, multi->stripes[0].physical);
405 if (ret != *len)
406 ret = -EIO;
407 else
408 ret = 0;
409 err:
410 kfree(multi);
411 return ret;
412 }
413
414 int write_and_map_eb(struct btrfs_fs_info *fs_info, struct extent_buffer *eb)
415 {
416 int ret;
417 int dev_nr;
418 u64 length;
419 u64 *raid_map = NULL;
420 struct btrfs_multi_bio *multi = NULL;
421
422 dev_nr = 0;
423 length = eb->len;
424 ret = btrfs_map_block(fs_info, WRITE, eb->start, &length,
425 &multi, 0, &raid_map);
426
427 if (raid_map) {
428 ret = write_raid56_with_parity(fs_info, eb, multi,
429 length, raid_map);
430 BUG_ON(ret);
431 } else while (dev_nr < multi->num_stripes) {
432 BUG_ON(ret);
433 eb->fd = multi->stripes[dev_nr].dev->fd;
434 eb->dev_bytenr = multi->stripes[dev_nr].physical;
435 multi->stripes[dev_nr].dev->total_ios++;
436 dev_nr++;
437 ret = write_extent_to_disk(eb);
438 BUG_ON(ret);
439 }
440 kfree(raid_map);
441 kfree(multi);
442 return 0;
443 }
444
445 int write_tree_block(struct btrfs_trans_handle *trans,
446 struct btrfs_fs_info *fs_info,
447 struct extent_buffer *eb)
448 {
449 if (check_tree_block(fs_info, eb)) {
450 print_tree_block_error(fs_info, eb,
451 check_tree_block(fs_info, eb));
452 BUG();
453 }
454
455 if (trans && !btrfs_buffer_uptodate(eb, trans->transid))
456 BUG();
457
458 btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
459 csum_tree_block(fs_info, eb, 0);
460
461 return write_and_map_eb(fs_info, eb);
462 }
463
464 void btrfs_setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
465 u64 objectid)
466 {
467 root->node = NULL;
468 root->commit_root = NULL;
469 root->ref_cows = 0;
470 root->track_dirty = 0;
471
472 root->fs_info = fs_info;
473 root->objectid = objectid;
474 root->last_trans = 0;
475 root->last_inode_alloc = 0;
476
477 INIT_LIST_HEAD(&root->dirty_list);
478 INIT_LIST_HEAD(&root->orphan_data_extents);
479 memset(&root->root_key, 0, sizeof(root->root_key));
480 memset(&root->root_item, 0, sizeof(root->root_item));
481 root->root_key.objectid = objectid;
482 }
483
484 static int find_and_setup_root(struct btrfs_root *tree_root,
485 struct btrfs_fs_info *fs_info,
486 u64 objectid, struct btrfs_root *root)
487 {
488 int ret;
489 u64 generation;
490
491 btrfs_setup_root(root, fs_info, objectid);
492 ret = btrfs_find_last_root(tree_root, objectid,
493 &root->root_item, &root->root_key);
494 if (ret)
495 return ret;
496
497 generation = btrfs_root_generation(&root->root_item);
498 root->node = read_tree_block(fs_info,
499 btrfs_root_bytenr(&root->root_item), generation);
500 if (!extent_buffer_uptodate(root->node))
501 return -EIO;
502
503 return 0;
504 }
505
506 static int find_and_setup_log_root(struct btrfs_root *tree_root,
507 struct btrfs_fs_info *fs_info,
508 struct btrfs_super_block *disk_super)
509 {
510 u64 blocknr = btrfs_super_log_root(disk_super);
511 struct btrfs_root *log_root = malloc(sizeof(struct btrfs_root));
512
513 if (!log_root)
514 return -ENOMEM;
515
516 if (blocknr == 0) {
517 free(log_root);
518 return 0;
519 }
520
521 btrfs_setup_root(log_root, fs_info,
522 BTRFS_TREE_LOG_OBJECTID);
523
524 log_root->node = read_tree_block(fs_info, blocknr,
525 btrfs_super_generation(disk_super) + 1);
526
527 fs_info->log_root_tree = log_root;
528
529 if (!extent_buffer_uptodate(log_root->node)) {
530 free_extent_buffer(log_root->node);
531 free(log_root);
532 fs_info->log_root_tree = NULL;
533 return -EIO;
534 }
535
536 return 0;
537 }
538
539 int btrfs_free_fs_root(struct btrfs_root *root)
540 {
541 if (root->node)
542 free_extent_buffer(root->node);
543 if (root->commit_root)
544 free_extent_buffer(root->commit_root);
545 kfree(root);
546 return 0;
547 }
548
549 static void __free_fs_root(struct rb_node *node)
550 {
551 struct btrfs_root *root;
552
553 root = container_of(node, struct btrfs_root, rb_node);
554 btrfs_free_fs_root(root);
555 }
556
557 FREE_RB_BASED_TREE(fs_roots, __free_fs_root);
558
559 struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
560 struct btrfs_key *location)
561 {
562 struct btrfs_root *root;
563 struct btrfs_root *tree_root = fs_info->tree_root;
564 struct btrfs_path *path;
565 struct extent_buffer *l;
566 u64 generation;
567 int ret = 0;
568
569 root = calloc(1, sizeof(*root));
570 if (!root)
571 return ERR_PTR(-ENOMEM);
572 if (location->offset == (u64)-1) {
573 ret = find_and_setup_root(tree_root, fs_info,
574 location->objectid, root);
575 if (ret) {
576 free(root);
577 return ERR_PTR(ret);
578 }
579 goto insert;
580 }
581
582 btrfs_setup_root(root, fs_info,
583 location->objectid);
584
585 path = btrfs_alloc_path();
586 if (!path) {
587 free(root);
588 return ERR_PTR(-ENOMEM);
589 }
590
591 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
592 if (ret != 0) {
593 if (ret > 0)
594 ret = -ENOENT;
595 goto out;
596 }
597 l = path->nodes[0];
598 read_extent_buffer(l, &root->root_item,
599 btrfs_item_ptr_offset(l, path->slots[0]),
600 sizeof(root->root_item));
601 memcpy(&root->root_key, location, sizeof(*location));
602 ret = 0;
603 out:
604 btrfs_free_path(path);
605 if (ret) {
606 free(root);
607 return ERR_PTR(ret);
608 }
609 generation = btrfs_root_generation(&root->root_item);
610 root->node = read_tree_block(fs_info,
611 btrfs_root_bytenr(&root->root_item), generation);
612 if (!extent_buffer_uptodate(root->node)) {
613 free(root);
614 return ERR_PTR(-EIO);
615 }
616 insert:
617 root->ref_cows = 1;
618 return root;
619 }
620
621 static int btrfs_fs_roots_compare_objectids(struct rb_node *node,
622 void *data)
623 {
624 u64 objectid = *((u64 *)data);
625 struct btrfs_root *root;
626
627 root = rb_entry(node, struct btrfs_root, rb_node);
628 if (objectid > root->objectid)
629 return 1;
630 else if (objectid < root->objectid)
631 return -1;
632 else
633 return 0;
634 }
635
636 static int btrfs_fs_roots_compare_roots(struct rb_node *node1,
637 struct rb_node *node2)
638 {
639 struct btrfs_root *root;
640
641 root = rb_entry(node2, struct btrfs_root, rb_node);
642 return btrfs_fs_roots_compare_objectids(node1, (void *)&root->objectid);
643 }
644
645 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
646 struct btrfs_key *location)
647 {
648 struct btrfs_root *root;
649 struct rb_node *node;
650 int ret;
651 u64 objectid = location->objectid;
652
653 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
654 return fs_info->tree_root;
655 if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
656 return fs_info->extent_root;
657 if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
658 return fs_info->chunk_root;
659 if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
660 return fs_info->dev_root;
661 if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
662 return fs_info->csum_root;
663 if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
664 return fs_info->quota_enabled ? fs_info->quota_root :
665 ERR_PTR(-ENOENT);
666
667 BUG_ON(location->objectid == BTRFS_TREE_RELOC_OBJECTID ||
668 location->offset != (u64)-1);
669
670 node = rb_search(&fs_info->fs_root_tree, (void *)&objectid,
671 btrfs_fs_roots_compare_objectids, NULL);
672 if (node)
673 return container_of(node, struct btrfs_root, rb_node);
674
675 root = btrfs_read_fs_root_no_cache(fs_info, location);
676 if (IS_ERR(root))
677 return root;
678
679 ret = rb_insert(&fs_info->fs_root_tree, &root->rb_node,
680 btrfs_fs_roots_compare_roots);
681 BUG_ON(ret);
682 return root;
683 }
684
685 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
686 {
687 if (fs_info->quota_root)
688 free(fs_info->quota_root);
689
690 free(fs_info->tree_root);
691 free(fs_info->extent_root);
692 free(fs_info->chunk_root);
693 free(fs_info->dev_root);
694 free(fs_info->csum_root);
695 free(fs_info->free_space_root);
696 free(fs_info->super_copy);
697 free(fs_info->log_root_tree);
698 free(fs_info);
699 }
700
701 struct btrfs_fs_info *btrfs_new_fs_info(int writable, u64 sb_bytenr)
702 {
703 struct btrfs_fs_info *fs_info;
704
705 fs_info = calloc(1, sizeof(struct btrfs_fs_info));
706 if (!fs_info)
707 return NULL;
708
709 fs_info->tree_root = calloc(1, sizeof(struct btrfs_root));
710 fs_info->extent_root = calloc(1, sizeof(struct btrfs_root));
711 fs_info->chunk_root = calloc(1, sizeof(struct btrfs_root));
712 fs_info->dev_root = calloc(1, sizeof(struct btrfs_root));
713 fs_info->csum_root = calloc(1, sizeof(struct btrfs_root));
714 fs_info->quota_root = calloc(1, sizeof(struct btrfs_root));
715 fs_info->free_space_root = calloc(1, sizeof(struct btrfs_root));
716 fs_info->super_copy = calloc(1, BTRFS_SUPER_INFO_SIZE);
717
718 if (!fs_info->tree_root || !fs_info->extent_root ||
719 !fs_info->chunk_root || !fs_info->dev_root ||
720 !fs_info->csum_root || !fs_info->quota_root ||
721 !fs_info->free_space_root || !fs_info->super_copy)
722 goto free_all;
723
724 extent_io_tree_init(&fs_info->extent_cache);
725 extent_io_tree_init(&fs_info->free_space_cache);
726 extent_io_tree_init(&fs_info->block_group_cache);
727 extent_io_tree_init(&fs_info->pinned_extents);
728 extent_io_tree_init(&fs_info->pending_del);
729 extent_io_tree_init(&fs_info->extent_ins);
730 fs_info->excluded_extents = NULL;
731
732 fs_info->fs_root_tree = RB_ROOT;
733 cache_tree_init(&fs_info->mapping_tree.cache_tree);
734
735 mutex_init(&fs_info->fs_mutex);
736 INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
737 INIT_LIST_HEAD(&fs_info->space_info);
738 INIT_LIST_HEAD(&fs_info->recow_ebs);
739
740 if (!writable)
741 fs_info->readonly = 1;
742
743 fs_info->super_bytenr = sb_bytenr;
744 fs_info->data_alloc_profile = (u64)-1;
745 fs_info->metadata_alloc_profile = (u64)-1;
746 fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
747 return fs_info;
748 free_all:
749 btrfs_free_fs_info(fs_info);
750 return NULL;
751 }
752
753 int btrfs_check_fs_compatibility(struct btrfs_super_block *sb,
754 unsigned int flags)
755 {
756 u64 features;
757
758 features = btrfs_super_incompat_flags(sb) &
759 ~BTRFS_FEATURE_INCOMPAT_SUPP;
760 if (features) {
761 printk("couldn't open because of unsupported "
762 "option features (%Lx).\n",
763 (unsigned long long)features);
764 return -ENOTSUP;
765 }
766
767 features = btrfs_super_incompat_flags(sb);
768 if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
769 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
770 btrfs_set_super_incompat_flags(sb, features);
771 }
772
773 features = btrfs_super_compat_ro_flags(sb);
774 if (flags & OPEN_CTREE_WRITES) {
775 if (flags & OPEN_CTREE_INVALIDATE_FST) {
776 /* Clear the FREE_SPACE_TREE_VALID bit on disk... */
777 features &= ~BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID;
778 btrfs_set_super_compat_ro_flags(sb, features);
779 /* ... and ignore the free space tree bit. */
780 features &= ~BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE;
781 }
782 if (features & ~BTRFS_FEATURE_COMPAT_RO_SUPP) {
783 printk("couldn't open RDWR because of unsupported "
784 "option features (%Lx).\n",
785 (unsigned long long)features);
786 return -ENOTSUP;
787 }
788
789 }
790 return 0;
791 }
792
793 static int find_best_backup_root(struct btrfs_super_block *super)
794 {
795 struct btrfs_root_backup *backup;
796 u64 orig_gen = btrfs_super_generation(super);
797 u64 gen = 0;
798 int best_index = 0;
799 int i;
800
801 for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
802 backup = super->super_roots + i;
803 if (btrfs_backup_tree_root_gen(backup) != orig_gen &&
804 btrfs_backup_tree_root_gen(backup) > gen) {
805 best_index = i;
806 gen = btrfs_backup_tree_root_gen(backup);
807 }
808 }
809 return best_index;
810 }
811
812 static int setup_root_or_create_block(struct btrfs_fs_info *fs_info,
813 unsigned flags,
814 struct btrfs_root *info_root,
815 u64 objectid, char *str)
816 {
817 struct btrfs_root *root = fs_info->tree_root;
818 int ret;
819
820 ret = find_and_setup_root(root, fs_info, objectid, info_root);
821 if (ret) {
822 printk("Couldn't setup %s tree\n", str);
823 if (!(flags & OPEN_CTREE_PARTIAL))
824 return -EIO;
825 /*
826 * Need a blank node here just so we don't screw up in the
827 * million of places that assume a root has a valid ->node
828 */
829 info_root->node =
830 btrfs_find_create_tree_block(fs_info, 0);
831 if (!info_root->node)
832 return -ENOMEM;
833 clear_extent_buffer_uptodate(info_root->node);
834 }
835
836 return 0;
837 }
838
839 int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info, u64 root_tree_bytenr,
840 unsigned flags)
841 {
842 struct btrfs_super_block *sb = fs_info->super_copy;
843 struct btrfs_root *root;
844 struct btrfs_key key;
845 u64 generation;
846 int ret;
847
848 root = fs_info->tree_root;
849 btrfs_setup_root(root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
850 generation = btrfs_super_generation(sb);
851
852 if (!root_tree_bytenr && !(flags & OPEN_CTREE_BACKUP_ROOT)) {
853 root_tree_bytenr = btrfs_super_root(sb);
854 } else if (flags & OPEN_CTREE_BACKUP_ROOT) {
855 struct btrfs_root_backup *backup;
856 int index = find_best_backup_root(sb);
857 if (index >= BTRFS_NUM_BACKUP_ROOTS) {
858 fprintf(stderr, "Invalid backup root number\n");
859 return -EIO;
860 }
861 backup = fs_info->super_copy->super_roots + index;
862 root_tree_bytenr = btrfs_backup_tree_root(backup);
863 generation = btrfs_backup_tree_root_gen(backup);
864 }
865
866 root->node = read_tree_block(fs_info, root_tree_bytenr, generation);
867 if (!extent_buffer_uptodate(root->node)) {
868 fprintf(stderr, "Couldn't read tree root\n");
869 return -EIO;
870 }
871
872 ret = setup_root_or_create_block(fs_info, flags, fs_info->extent_root,
873 BTRFS_EXTENT_TREE_OBJECTID, "extent");
874 if (ret)
875 return ret;
876 fs_info->extent_root->track_dirty = 1;
877
878 ret = find_and_setup_root(root, fs_info, BTRFS_DEV_TREE_OBJECTID,
879 fs_info->dev_root);
880 if (ret) {
881 printk("Couldn't setup device tree\n");
882 return -EIO;
883 }
884 fs_info->dev_root->track_dirty = 1;
885
886 ret = setup_root_or_create_block(fs_info, flags, fs_info->csum_root,
887 BTRFS_CSUM_TREE_OBJECTID, "csum");
888 if (ret)
889 return ret;
890 fs_info->csum_root->track_dirty = 1;
891
892 ret = find_and_setup_root(root, fs_info, BTRFS_QUOTA_TREE_OBJECTID,
893 fs_info->quota_root);
894 if (ret) {
895 free(fs_info->quota_root);
896 fs_info->quota_root = NULL;
897 } else {
898 fs_info->quota_enabled = 1;
899 }
900
901 if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
902 ret = find_and_setup_root(root, fs_info, BTRFS_FREE_SPACE_TREE_OBJECTID,
903 fs_info->free_space_root);
904 if (ret) {
905 printk("Couldn't read free space tree\n");
906 return -EIO;
907 }
908 fs_info->free_space_root->track_dirty = 1;
909 }
910
911 ret = find_and_setup_log_root(root, fs_info, sb);
912 if (ret) {
913 printk("Couldn't setup log root tree\n");
914 if (!(flags & OPEN_CTREE_PARTIAL))
915 return -EIO;
916 }
917
918 fs_info->generation = generation;
919 fs_info->last_trans_committed = generation;
920 if (extent_buffer_uptodate(fs_info->extent_root->node) &&
921 !(flags & OPEN_CTREE_NO_BLOCK_GROUPS)) {
922 ret = btrfs_read_block_groups(fs_info->tree_root);
923 /*
924 * If we don't find any blockgroups (ENOENT) we're either
925 * restoring or creating the filesystem, where it's expected,
926 * anything else is error
927 */
928 if (ret != -ENOENT)
929 return -EIO;
930 }
931
932 key.objectid = BTRFS_FS_TREE_OBJECTID;
933 key.type = BTRFS_ROOT_ITEM_KEY;
934 key.offset = (u64)-1;
935 fs_info->fs_root = btrfs_read_fs_root(fs_info, &key);
936
937 if (IS_ERR(fs_info->fs_root))
938 return -EIO;
939 return 0;
940 }
941
942 void btrfs_release_all_roots(struct btrfs_fs_info *fs_info)
943 {
944 if (fs_info->free_space_root)
945 free_extent_buffer(fs_info->free_space_root->node);
946 if (fs_info->quota_root)
947 free_extent_buffer(fs_info->quota_root->node);
948 if (fs_info->csum_root)
949 free_extent_buffer(fs_info->csum_root->node);
950 if (fs_info->dev_root)
951 free_extent_buffer(fs_info->dev_root->node);
952 if (fs_info->extent_root)
953 free_extent_buffer(fs_info->extent_root->node);
954 if (fs_info->tree_root)
955 free_extent_buffer(fs_info->tree_root->node);
956 if (fs_info->log_root_tree)
957 free_extent_buffer(fs_info->log_root_tree->node);
958 if (fs_info->chunk_root)
959 free_extent_buffer(fs_info->chunk_root->node);
960 }
961
962 static void free_map_lookup(struct cache_extent *ce)
963 {
964 struct map_lookup *map;
965
966 map = container_of(ce, struct map_lookup, ce);
967 kfree(map);
968 }
969
970 FREE_EXTENT_CACHE_BASED_TREE(mapping_cache, free_map_lookup);
971
972 void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info)
973 {
974 while (!list_empty(&fs_info->recow_ebs)) {
975 struct extent_buffer *eb;
976 eb = list_first_entry(&fs_info->recow_ebs,
977 struct extent_buffer, recow);
978 list_del_init(&eb->recow);
979 free_extent_buffer(eb);
980 }
981 free_mapping_cache_tree(&fs_info->mapping_tree.cache_tree);
982 extent_io_tree_cleanup(&fs_info->extent_cache);
983 extent_io_tree_cleanup(&fs_info->free_space_cache);
984 extent_io_tree_cleanup(&fs_info->block_group_cache);
985 extent_io_tree_cleanup(&fs_info->pinned_extents);
986 extent_io_tree_cleanup(&fs_info->pending_del);
987 extent_io_tree_cleanup(&fs_info->extent_ins);
988 }
989
990 int btrfs_scan_fs_devices(int fd, const char *path,
991 struct btrfs_fs_devices **fs_devices,
992 u64 sb_bytenr, unsigned sbflags,
993 int skip_devices)
994 {
995 u64 total_devs;
996 u64 dev_size;
997 off_t seek_ret;
998 int ret;
999 if (!sb_bytenr)
1000 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
1001
1002 seek_ret = lseek(fd, 0, SEEK_END);
1003 if (seek_ret < 0)
1004 return -errno;
1005
1006 dev_size = seek_ret;
1007 lseek(fd, 0, SEEK_SET);
1008 if (sb_bytenr > dev_size) {
1009 error("superblock bytenr %llu is larger than device size %llu",
1010 (unsigned long long)sb_bytenr,
1011 (unsigned long long)dev_size);
1012 return -EINVAL;
1013 }
1014
1015 ret = btrfs_scan_one_device(fd, path, fs_devices,
1016 &total_devs, sb_bytenr, sbflags);
1017 if (ret) {
1018 fprintf(stderr, "No valid Btrfs found on %s\n", path);
1019 return ret;
1020 }
1021
1022 if (!skip_devices && total_devs != 1) {
1023 ret = btrfs_scan_devices();
1024 if (ret)
1025 return ret;
1026 }
1027 return 0;
1028 }
1029
1030 int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info,
1031 u64 chunk_root_bytenr)
1032 {
1033 struct btrfs_super_block *sb = fs_info->super_copy;
1034 u64 generation;
1035 int ret;
1036
1037 btrfs_setup_root(fs_info->chunk_root, fs_info,
1038 BTRFS_CHUNK_TREE_OBJECTID);
1039
1040 ret = btrfs_read_sys_array(fs_info);
1041 if (ret)
1042 return ret;
1043
1044 generation = btrfs_super_chunk_root_generation(sb);
1045
1046 if (chunk_root_bytenr && !IS_ALIGNED(chunk_root_bytenr,
1047 fs_info->sectorsize)) {
1048 warning("chunk_root_bytenr %llu is unaligned to %u, ignore it",
1049 chunk_root_bytenr, fs_info->sectorsize);
1050 chunk_root_bytenr = 0;
1051 }
1052
1053 if (!chunk_root_bytenr)
1054 chunk_root_bytenr = btrfs_super_chunk_root(sb);
1055 else
1056 generation = 0;
1057
1058 fs_info->chunk_root->node = read_tree_block(fs_info,
1059 chunk_root_bytenr,
1060 generation);
1061 if (!extent_buffer_uptodate(fs_info->chunk_root->node)) {
1062 if (fs_info->ignore_chunk_tree_error) {
1063 warning("cannot read chunk root, continue anyway");
1064 fs_info->chunk_root = NULL;
1065 return 0;
1066 } else {
1067 error("cannot read chunk root");
1068 return -EIO;
1069 }
1070 }
1071
1072 if (!(btrfs_super_flags(sb) & BTRFS_SUPER_FLAG_METADUMP)) {
1073 ret = btrfs_read_chunk_tree(fs_info);
1074 if (ret) {
1075 fprintf(stderr, "Couldn't read chunk tree\n");
1076 return ret;
1077 }
1078 }
1079 return 0;
1080 }
1081
1082 static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
1083 u64 sb_bytenr,
1084 u64 root_tree_bytenr,
1085 u64 chunk_root_bytenr,
1086 unsigned flags)
1087 {
1088 struct btrfs_fs_info *fs_info;
1089 struct btrfs_super_block *disk_super;
1090 struct btrfs_fs_devices *fs_devices = NULL;
1091 struct extent_buffer *eb;
1092 int ret;
1093 int oflags;
1094 unsigned sbflags = SBREAD_DEFAULT;
1095
1096 if (sb_bytenr == 0)
1097 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
1098
1099 /* try to drop all the caches */
1100 if (posix_fadvise(fp, 0, 0, POSIX_FADV_DONTNEED))
1101 fprintf(stderr, "Warning, could not drop caches\n");
1102
1103 fs_info = btrfs_new_fs_info(flags & OPEN_CTREE_WRITES, sb_bytenr);
1104 if (!fs_info) {
1105 fprintf(stderr, "Failed to allocate memory for fs_info\n");
1106 return NULL;
1107 }
1108 if (flags & OPEN_CTREE_RESTORE)
1109 fs_info->on_restoring = 1;
1110 if (flags & OPEN_CTREE_SUPPRESS_CHECK_BLOCK_ERRORS)
1111 fs_info->suppress_check_block_errors = 1;
1112 if (flags & OPEN_CTREE_IGNORE_FSID_MISMATCH)
1113 fs_info->ignore_fsid_mismatch = 1;
1114 if (flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR)
1115 fs_info->ignore_chunk_tree_error = 1;
1116
1117 if ((flags & OPEN_CTREE_RECOVER_SUPER)
1118 && (flags & OPEN_CTREE_FS_PARTIAL)) {
1119 fprintf(stderr,
1120 "cannot open a partially created filesystem for recovery");
1121 goto out;
1122 }
1123
1124 if (flags & OPEN_CTREE_FS_PARTIAL)
1125 sbflags = SBREAD_PARTIAL;
1126
1127 ret = btrfs_scan_fs_devices(fp, path, &fs_devices, sb_bytenr, sbflags,
1128 (flags & OPEN_CTREE_NO_DEVICES));
1129 if (ret)
1130 goto out;
1131
1132 fs_info->fs_devices = fs_devices;
1133 if (flags & OPEN_CTREE_WRITES)
1134 oflags = O_RDWR;
1135 else
1136 oflags = O_RDONLY;
1137
1138 if (flags & OPEN_CTREE_EXCLUSIVE)
1139 oflags |= O_EXCL;
1140
1141 ret = btrfs_open_devices(fs_devices, oflags);
1142 if (ret)
1143 goto out;
1144
1145 disk_super = fs_info->super_copy;
1146 if (flags & OPEN_CTREE_RECOVER_SUPER)
1147 ret = btrfs_read_dev_super(fs_devices->latest_bdev, disk_super,
1148 sb_bytenr, SBREAD_RECOVER);
1149 else
1150 ret = btrfs_read_dev_super(fp, disk_super, sb_bytenr,
1151 sbflags);
1152 if (ret) {
1153 printk("No valid btrfs found\n");
1154 goto out_devices;
1155 }
1156
1157 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID &&
1158 !fs_info->ignore_fsid_mismatch) {
1159 fprintf(stderr, "ERROR: Filesystem UUID change in progress\n");
1160 goto out_devices;
1161 }
1162
1163 memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
1164 fs_info->sectorsize = btrfs_super_sectorsize(disk_super);
1165 fs_info->nodesize = btrfs_super_nodesize(disk_super);
1166 fs_info->stripesize = btrfs_super_stripesize(disk_super);
1167
1168 ret = btrfs_check_fs_compatibility(fs_info->super_copy, flags);
1169 if (ret)
1170 goto out_devices;
1171
1172 ret = btrfs_setup_chunk_tree_and_device_map(fs_info, chunk_root_bytenr);
1173 if (ret)
1174 goto out_chunk;
1175
1176 /* Chunk tree root is unable to read, return directly */
1177 if (!fs_info->chunk_root)
1178 return fs_info;
1179
1180 eb = fs_info->chunk_root->node;
1181 read_extent_buffer(eb, fs_info->chunk_tree_uuid,
1182 btrfs_header_chunk_tree_uuid(eb),
1183 BTRFS_UUID_SIZE);
1184
1185 ret = btrfs_setup_all_roots(fs_info, root_tree_bytenr, flags);
1186 if (ret && !(flags & __OPEN_CTREE_RETURN_CHUNK_ROOT) &&
1187 !fs_info->ignore_chunk_tree_error)
1188 goto out_chunk;
1189
1190 return fs_info;
1191
1192 out_chunk:
1193 btrfs_release_all_roots(fs_info);
1194 btrfs_cleanup_all_caches(fs_info);
1195 out_devices:
1196 btrfs_close_devices(fs_devices);
1197 out:
1198 btrfs_free_fs_info(fs_info);
1199 return NULL;
1200 }
1201
1202 struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
1203 u64 sb_bytenr, u64 root_tree_bytenr,
1204 u64 chunk_root_bytenr,
1205 unsigned flags)
1206 {
1207 int fp;
1208 int ret;
1209 struct btrfs_fs_info *info;
1210 int oflags = O_RDWR;
1211 struct stat st;
1212
1213 ret = stat(filename, &st);
1214 if (ret < 0) {
1215 error("cannot stat '%s': %m", filename);
1216 return NULL;
1217 }
1218 if (!(((st.st_mode & S_IFMT) == S_IFREG) || ((st.st_mode & S_IFMT) == S_IFBLK))) {
1219 error("not a regular file or block device: %s", filename);
1220 return NULL;
1221 }
1222
1223 if (!(flags & OPEN_CTREE_WRITES))
1224 oflags = O_RDONLY;
1225
1226 fp = open(filename, oflags);
1227 if (fp < 0) {
1228 error("cannot open '%s': %m", filename);
1229 return NULL;
1230 }
1231 info = __open_ctree_fd(fp, filename, sb_bytenr, root_tree_bytenr,
1232 chunk_root_bytenr, flags);
1233 close(fp);
1234 return info;
1235 }
1236
1237 struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr,
1238 unsigned flags)
1239 {
1240 struct btrfs_fs_info *info;
1241
1242 /* This flags may not return fs_info with any valid root */
1243 BUG_ON(flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR);
1244 info = open_ctree_fs_info(filename, sb_bytenr, 0, 0, flags);
1245 if (!info)
1246 return NULL;
1247 if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
1248 return info->chunk_root;
1249 return info->fs_root;
1250 }
1251
1252 struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
1253 unsigned flags)
1254 {
1255 struct btrfs_fs_info *info;
1256
1257 /* This flags may not return fs_info with any valid root */
1258 if (flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR) {
1259 error("invalid open_ctree flags: 0x%llx",
1260 (unsigned long long)flags);
1261 return NULL;
1262 }
1263 info = __open_ctree_fd(fp, path, sb_bytenr, 0, 0, flags);
1264 if (!info)
1265 return NULL;
1266 if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
1267 return info->chunk_root;
1268 return info->fs_root;
1269 }
1270
1271 /*
1272 * Check if the super is valid:
1273 * - nodesize/sectorsize - minimum, maximum, alignment
1274 * - tree block starts - alignment
1275 * - number of devices - something sane
1276 * - sys array size - maximum
1277 */
1278 static int check_super(struct btrfs_super_block *sb, unsigned sbflags)
1279 {
1280 u8 result[BTRFS_CSUM_SIZE];
1281 u32 crc;
1282 u16 csum_type;
1283 int csum_size;
1284
1285 if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
1286 if (btrfs_super_magic(sb) == BTRFS_MAGIC_PARTIAL) {
1287 if (!(sbflags & SBREAD_PARTIAL)) {
1288 error("superblock magic doesn't match");
1289 return -EIO;
1290 }
1291 }
1292 }
1293
1294 csum_type = btrfs_super_csum_type(sb);
1295 if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) {
1296 error("unsupported checksum algorithm %u", csum_type);
1297 return -EIO;
1298 }
1299 csum_size = btrfs_csum_sizes[csum_type];
1300
1301 crc = ~(u32)0;
1302 crc = btrfs_csum_data((char *)sb + BTRFS_CSUM_SIZE, crc,
1303 BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1304 btrfs_csum_final(crc, result);
1305
1306 if (memcmp(result, sb->csum, csum_size)) {
1307 error("superblock checksum mismatch");
1308 return -EIO;
1309 }
1310 if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
1311 error("tree_root level too big: %d >= %d",
1312 btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
1313 goto error_out;
1314 }
1315 if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
1316 error("chunk_root level too big: %d >= %d",
1317 btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
1318 goto error_out;
1319 }
1320 if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
1321 error("log_root level too big: %d >= %d",
1322 btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
1323 goto error_out;
1324 }
1325
1326 if (!IS_ALIGNED(btrfs_super_root(sb), 4096)) {
1327 error("tree_root block unaligned: %llu", btrfs_super_root(sb));
1328 goto error_out;
1329 }
1330 if (!IS_ALIGNED(btrfs_super_chunk_root(sb), 4096)) {
1331 error("chunk_root block unaligned: %llu",
1332 btrfs_super_chunk_root(sb));
1333 goto error_out;
1334 }
1335 if (!IS_ALIGNED(btrfs_super_log_root(sb), 4096)) {
1336 error("log_root block unaligned: %llu",
1337 btrfs_super_log_root(sb));
1338 goto error_out;
1339 }
1340 if (btrfs_super_nodesize(sb) < 4096) {
1341 error("nodesize too small: %u < 4096",
1342 btrfs_super_nodesize(sb));
1343 goto error_out;
1344 }
1345 if (!IS_ALIGNED(btrfs_super_nodesize(sb), 4096)) {
1346 error("nodesize unaligned: %u", btrfs_super_nodesize(sb));
1347 goto error_out;
1348 }
1349 if (btrfs_super_sectorsize(sb) < 4096) {
1350 error("sectorsize too small: %u < 4096",
1351 btrfs_super_sectorsize(sb));
1352 goto error_out;
1353 }
1354 if (!IS_ALIGNED(btrfs_super_sectorsize(sb), 4096)) {
1355 error("sectorsize unaligned: %u", btrfs_super_sectorsize(sb));
1356 goto error_out;
1357 }
1358 if (btrfs_super_total_bytes(sb) == 0) {
1359 error("invalid total_bytes 0");
1360 goto error_out;
1361 }
1362 if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
1363 error("invalid bytes_used %llu", btrfs_super_bytes_used(sb));
1364 goto error_out;
1365 }
1366 if ((btrfs_super_stripesize(sb) != 4096)
1367 && (btrfs_super_stripesize(sb) != btrfs_super_sectorsize(sb))) {
1368 error("invalid stripesize %u", btrfs_super_stripesize(sb));
1369 goto error_out;
1370 }
1371
1372 if (memcmp(sb->fsid, sb->dev_item.fsid, BTRFS_UUID_SIZE) != 0) {
1373 char fsid[BTRFS_UUID_UNPARSED_SIZE];
1374 char dev_fsid[BTRFS_UUID_UNPARSED_SIZE];
1375
1376 uuid_unparse(sb->fsid, fsid);
1377 uuid_unparse(sb->dev_item.fsid, dev_fsid);
1378 error("dev_item UUID does not match fsid: %s != %s",
1379 dev_fsid, fsid);
1380 goto error_out;
1381 }
1382
1383 /*
1384 * Hint to catch really bogus numbers, bitflips or so
1385 */
1386 if (btrfs_super_num_devices(sb) > (1UL << 31)) {
1387 warning("suspicious number of devices: %llu",
1388 btrfs_super_num_devices(sb));
1389 }
1390
1391 if (btrfs_super_num_devices(sb) == 0) {
1392 error("number of devices is 0");
1393 goto error_out;
1394 }
1395
1396 /*
1397 * Obvious sys_chunk_array corruptions, it must hold at least one key
1398 * and one chunk
1399 */
1400 if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
1401 error("system chunk array too big %u > %u",
1402 btrfs_super_sys_array_size(sb),
1403 BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
1404 goto error_out;
1405 }
1406 if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
1407 + sizeof(struct btrfs_chunk)) {
1408 error("system chunk array too small %u < %zu",
1409 btrfs_super_sys_array_size(sb),
1410 sizeof(struct btrfs_disk_key) +
1411 sizeof(struct btrfs_chunk));
1412 goto error_out;
1413 }
1414
1415 return 0;
1416
1417 error_out:
1418 error("superblock checksum matches but it has invalid members");
1419 return -EIO;
1420 }
1421
1422 /*
1423 * btrfs_read_dev_super - read a valid superblock from a block device
1424 * @fd: file descriptor of the device
1425 * @sb: buffer where the superblock is going to be read in
1426 * @sb_bytenr: offset of the particular superblock copy we want
1427 * @sbflags: flags controlling how the superblock is read
1428 *
1429 * This function is used by various btrfs comands to obtain a valid superblock.
1430 *
1431 * It's mode of operation is controlled by the @sb_bytenr and @sbdflags
1432 * parameters. If SBREAD_RECOVER flag is set and @sb_bytenr is
1433 * BTRFS_SUPER_INFO_OFFSET then the function reads all 3 superblock copies and
1434 * returns the newest one. If SBREAD_RECOVER is not set then only a single
1435 * copy is read, which one is decided by @sb_bytenr. If @sb_bytenr !=
1436 * BTRFS_SUPER_INFO_OFFSET then the @sbflags is effectively ignored and only a
1437 * single copy is read.
1438 */
1439 int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr,
1440 unsigned sbflags)
1441 {
1442 u8 fsid[BTRFS_FSID_SIZE];
1443 int fsid_is_initialized = 0;
1444 char tmp[BTRFS_SUPER_INFO_SIZE];
1445 struct btrfs_super_block *buf = (struct btrfs_super_block *)tmp;
1446 int i;
1447 int ret;
1448 int max_super = sbflags & SBREAD_RECOVER ? BTRFS_SUPER_MIRROR_MAX : 1;
1449 u64 transid = 0;
1450 u64 bytenr;
1451
1452 if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) {
1453 ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
1454 /* real error */
1455 if (ret < 0)
1456 return -errno;
1457
1458 /* Not large enough sb, return -ENOENT instead of normal -EIO */
1459 if (ret < BTRFS_SUPER_INFO_SIZE)
1460 return -ENOENT;
1461
1462 if (btrfs_super_bytenr(buf) != sb_bytenr)
1463 return -EIO;
1464
1465 ret = check_super(buf, sbflags);
1466 if (ret < 0)
1467 return ret;
1468 memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE);
1469 return 0;
1470 }
1471
1472 /*
1473 * we would like to check all the supers, but that would make
1474 * a btrfs mount succeed after a mkfs from a different FS.
1475 * So, we need to add a special mount option to scan for
1476 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
1477 */
1478
1479 for (i = 0; i < max_super; i++) {
1480 bytenr = btrfs_sb_offset(i);
1481 ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, bytenr);
1482 if (ret < BTRFS_SUPER_INFO_SIZE)
1483 break;
1484
1485 if (btrfs_super_bytenr(buf) != bytenr )
1486 continue;
1487 /* if magic is NULL, the device was removed */
1488 if (btrfs_super_magic(buf) == 0 && i == 0)
1489 break;
1490 if (check_super(buf, sbflags))
1491 continue;
1492
1493 if (!fsid_is_initialized) {
1494 memcpy(fsid, buf->fsid, sizeof(fsid));
1495 fsid_is_initialized = 1;
1496 } else if (memcmp(fsid, buf->fsid, sizeof(fsid))) {
1497 /*
1498 * the superblocks (the original one and
1499 * its backups) contain data of different
1500 * filesystems -> the super cannot be trusted
1501 */
1502 continue;
1503 }
1504
1505 if (btrfs_super_generation(buf) > transid) {
1506 memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE);
1507 transid = btrfs_super_generation(buf);
1508 }
1509 }
1510
1511 return transid > 0 ? 0 : -1;
1512 }
1513
1514 static int write_dev_supers(struct btrfs_fs_info *fs_info,
1515 struct btrfs_super_block *sb,
1516 struct btrfs_device *device)
1517 {
1518 u64 bytenr;
1519 u32 crc;
1520 int i, ret;
1521
1522 if (fs_info->super_bytenr != BTRFS_SUPER_INFO_OFFSET) {
1523 btrfs_set_super_bytenr(sb, fs_info->super_bytenr);
1524 crc = ~(u32)0;
1525 crc = btrfs_csum_data((char *)sb + BTRFS_CSUM_SIZE, crc,
1526 BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1527 btrfs_csum_final(crc, &sb->csum[0]);
1528
1529 /*
1530 * super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
1531 * zero filled, we can use it directly
1532 */
1533 ret = pwrite64(device->fd, fs_info->super_copy,
1534 BTRFS_SUPER_INFO_SIZE,
1535 fs_info->super_bytenr);
1536 if (ret != BTRFS_SUPER_INFO_SIZE)
1537 goto write_err;
1538 return 0;
1539 }
1540
1541 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1542 bytenr = btrfs_sb_offset(i);
1543 if (bytenr + BTRFS_SUPER_INFO_SIZE > device->total_bytes)
1544 break;
1545
1546 btrfs_set_super_bytenr(sb, bytenr);
1547
1548 crc = ~(u32)0;
1549 crc = btrfs_csum_data((char *)sb + BTRFS_CSUM_SIZE, crc,
1550 BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1551 btrfs_csum_final(crc, &sb->csum[0]);
1552
1553 /*
1554 * super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
1555 * zero filled, we can use it directly
1556 */
1557 ret = pwrite64(device->fd, fs_info->super_copy,
1558 BTRFS_SUPER_INFO_SIZE, bytenr);
1559 if (ret != BTRFS_SUPER_INFO_SIZE)
1560 goto write_err;
1561 }
1562
1563 return 0;
1564
1565 write_err:
1566 if (ret > 0)
1567 fprintf(stderr, "WARNING: failed to write all sb data\n");
1568 else
1569 fprintf(stderr, "WARNING: failed to write sb: %m\n");
1570 return ret;
1571 }
1572
1573 int write_all_supers(struct btrfs_fs_info *fs_info)
1574 {
1575 struct list_head *head = &fs_info->fs_devices->devices;
1576 struct btrfs_device *dev;
1577 struct btrfs_super_block *sb;
1578 struct btrfs_dev_item *dev_item;
1579 int ret;
1580 u64 flags;
1581
1582 sb = fs_info->super_copy;
1583 dev_item = &sb->dev_item;
1584 list_for_each_entry(dev, head, dev_list) {
1585 if (!dev->writeable)
1586 continue;
1587
1588 btrfs_set_stack_device_generation(dev_item, 0);
1589 btrfs_set_stack_device_type(dev_item, dev->type);
1590 btrfs_set_stack_device_id(dev_item, dev->devid);
1591 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
1592 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
1593 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
1594 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
1595 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
1596 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
1597 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
1598
1599 flags = btrfs_super_flags(sb);
1600 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
1601
1602 ret = write_dev_supers(fs_info, sb, dev);
1603 BUG_ON(ret);
1604 }
1605 return 0;
1606 }
1607
1608 int write_ctree_super(struct btrfs_trans_handle *trans,
1609 struct btrfs_fs_info *fs_info)
1610 {
1611 int ret;
1612 struct btrfs_root *tree_root = fs_info->tree_root;
1613 struct btrfs_root *chunk_root = fs_info->chunk_root;
1614
1615 if (fs_info->readonly)
1616 return 0;
1617
1618 btrfs_set_super_generation(fs_info->super_copy,
1619 trans->transid);
1620 btrfs_set_super_root(fs_info->super_copy,
1621 tree_root->node->start);
1622 btrfs_set_super_root_level(fs_info->super_copy,
1623 btrfs_header_level(tree_root->node));
1624 btrfs_set_super_chunk_root(fs_info->super_copy,
1625 chunk_root->node->start);
1626 btrfs_set_super_chunk_root_level(fs_info->super_copy,
1627 btrfs_header_level(chunk_root->node));
1628 btrfs_set_super_chunk_root_generation(fs_info->super_copy,
1629 btrfs_header_generation(chunk_root->node));
1630
1631 ret = write_all_supers(fs_info);
1632 if (ret)
1633 fprintf(stderr, "failed to write new super block err %d\n", ret);
1634 return ret;
1635 }
1636
1637 int close_ctree_fs_info(struct btrfs_fs_info *fs_info)
1638 {
1639 int ret;
1640 int err = 0;
1641 struct btrfs_trans_handle *trans;
1642 struct btrfs_root *root = fs_info->tree_root;
1643
1644 if (fs_info->last_trans_committed !=
1645 fs_info->generation) {
1646 BUG_ON(!root);
1647 trans = btrfs_start_transaction(root, 1);
1648 if (IS_ERR(trans)) {
1649 err = PTR_ERR(trans);
1650 goto skip_commit;
1651 }
1652 btrfs_commit_transaction(trans, root);
1653 trans = btrfs_start_transaction(root, 1);
1654 BUG_ON(IS_ERR(trans));
1655 ret = commit_tree_roots(trans, fs_info);
1656 BUG_ON(ret);
1657 ret = __commit_transaction(trans, root);
1658 BUG_ON(ret);
1659 write_ctree_super(trans, fs_info);
1660 kfree(trans);
1661 }
1662
1663 if (fs_info->finalize_on_close) {
1664 btrfs_set_super_magic(fs_info->super_copy, BTRFS_MAGIC);
1665 root->fs_info->finalize_on_close = 0;
1666 ret = write_all_supers(fs_info);
1667 if (ret)
1668 fprintf(stderr,
1669 "failed to write new super block err %d\n", ret);
1670 }
1671
1672 skip_commit:
1673 btrfs_free_block_groups(fs_info);
1674
1675 free_fs_roots_tree(&fs_info->fs_root_tree);
1676
1677 btrfs_release_all_roots(fs_info);
1678 ret = btrfs_close_devices(fs_info->fs_devices);
1679 btrfs_cleanup_all_caches(fs_info);
1680 btrfs_free_fs_info(fs_info);
1681 if (!err)
1682 err = ret;
1683 return err;
1684 }
1685
1686 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1687 struct extent_buffer *eb)
1688 {
1689 return clear_extent_buffer_dirty(eb);
1690 }
1691
1692 void btrfs_mark_buffer_dirty(struct extent_buffer *eb)
1693 {
1694 set_extent_buffer_dirty(eb);
1695 }
1696
1697 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
1698 {
1699 int ret;
1700
1701 ret = extent_buffer_uptodate(buf);
1702 if (!ret)
1703 return ret;
1704
1705 ret = verify_parent_transid(buf->tree, buf, parent_transid, 1);
1706 return !ret;
1707 }
1708
1709 int btrfs_set_buffer_uptodate(struct extent_buffer *eb)
1710 {
1711 return set_extent_buffer_uptodate(eb);
1712 }
(deprecated) Btrfs progs developments and patch integration