btrfs-progs: tests: test mkfs.btrfs fails on small backing size thin provision device
[btrfs-progs-unstable/devel.git] / disk-io.c
blob72d44531a1b5f3bd1c0c2dab122cb5fe5bafb54a
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
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.
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.
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.
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"
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)
43 /* Calculate max possible nritems for a leaf/node */
44 static u32 max_nritems(u8 level, u32 nodesize)
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));
54 static int check_tree_block(struct btrfs_fs_info *fs_info,
55 struct extent_buffer *buf)
58 struct btrfs_fs_devices *fs_devices;
59 u32 nodesize = fs_info->nodesize;
60 int ret = BTRFS_BAD_FSID;
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;
70 /* Only leaf can be empty */
71 if (btrfs_header_nritems(buf) == 0 &&
72 btrfs_header_level(buf) != 0)
73 return BTRFS_BAD_NRITEMS;
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;
84 fs_devices = fs_devices->seed;
86 return ret;
89 static void print_tree_block_error(struct btrfs_fs_info *fs_info,
90 struct extent_buffer *eb,
91 int err)
93 char fs_uuid[BTRFS_UUID_UNPARSED_SIZE] = {'\0'};
94 char found_uuid[BTRFS_UUID_UNPARSED_SIZE] = {'\0'};
95 u8 buf[BTRFS_UUID_SIZE];
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;
121 u32 btrfs_csum_data(char *data, u32 seed, size_t len)
123 return crc32c(seed, data, len);
126 void btrfs_csum_final(u32 crc, u8 *result)
128 put_unaligned_le32(~crc, result);
131 static int __csum_tree_block_size(struct extent_buffer *buf, u16 csum_size,
132 int verify, int silent)
134 u8 result[BTRFS_CSUM_SIZE];
135 u32 len;
136 u32 crc = ~(u32)0;
138 len = buf->len - BTRFS_CSUM_SIZE;
139 crc = crc32c(crc, buf->data + BTRFS_CSUM_SIZE, len);
140 btrfs_csum_final(crc, result);
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;
151 } else {
152 write_extent_buffer(buf, result, 0, csum_size);
154 return 0;
157 int csum_tree_block_size(struct extent_buffer *buf, u16 csum_size, int verify)
159 return __csum_tree_block_size(buf, csum_size, verify, 0);
162 int verify_tree_block_csum_silent(struct extent_buffer *buf, u16 csum_size)
164 return __csum_tree_block_size(buf, csum_size, 1, 1);
167 int csum_tree_block(struct btrfs_fs_info *fs_info,
168 struct extent_buffer *buf, int verify)
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);
177 struct extent_buffer *btrfs_find_tree_block(struct btrfs_fs_info *fs_info,
178 u64 bytenr, u32 blocksize)
180 return find_extent_buffer(&fs_info->extent_cache,
181 bytenr, blocksize);
184 struct extent_buffer* btrfs_find_create_tree_block(
185 struct btrfs_fs_info *fs_info, u64 bytenr)
187 return alloc_extent_buffer(fs_info, bytenr, fs_info->nodesize);
190 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
191 u64 parent_transid)
193 struct extent_buffer *eb;
194 u64 length;
195 struct btrfs_multi_bio *multi = NULL;
196 struct btrfs_device *device;
198 eb = btrfs_find_tree_block(fs_info, bytenr, fs_info->nodesize);
199 if (!(eb && btrfs_buffer_uptodate(eb, parent_transid)) &&
200 !btrfs_map_block(fs_info, READ, bytenr, &length, &multi, 0,
201 NULL)) {
202 device = multi->stripes[0].dev;
203 device->total_ios++;
204 readahead(device->fd, multi->stripes[0].physical,
205 fs_info->nodesize);
208 free_extent_buffer(eb);
209 kfree(multi);
212 static int verify_parent_transid(struct extent_io_tree *io_tree,
213 struct extent_buffer *eb, u64 parent_transid,
214 int ignore)
216 int ret;
218 if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
219 return 0;
221 if (extent_buffer_uptodate(eb) &&
222 btrfs_header_generation(eb) == parent_transid) {
223 ret = 0;
224 goto out;
226 printk("parent transid verify failed on %llu wanted %llu found %llu\n",
227 (unsigned long long)eb->start,
228 (unsigned long long)parent_transid,
229 (unsigned long long)btrfs_header_generation(eb));
230 if (ignore) {
231 eb->flags |= EXTENT_BAD_TRANSID;
232 printk("Ignoring transid failure\n");
233 return 0;
236 ret = 1;
237 out:
238 clear_extent_buffer_uptodate(eb);
239 return ret;
244 int read_whole_eb(struct btrfs_fs_info *info, struct extent_buffer *eb, int mirror)
246 unsigned long offset = 0;
247 struct btrfs_multi_bio *multi = NULL;
248 struct btrfs_device *device;
249 int ret = 0;
250 u64 read_len;
251 unsigned long bytes_left = eb->len;
253 while (bytes_left) {
254 read_len = bytes_left;
255 device = NULL;
257 if (!info->on_restoring &&
258 eb->start != BTRFS_SUPER_INFO_OFFSET) {
259 ret = btrfs_map_block(info, READ, eb->start + offset,
260 &read_len, &multi, mirror, NULL);
261 if (ret) {
262 printk("Couldn't map the block %Lu\n", eb->start + offset);
263 kfree(multi);
264 return -EIO;
266 device = multi->stripes[0].dev;
268 if (device->fd <= 0) {
269 kfree(multi);
270 return -EIO;
273 eb->fd = device->fd;
274 device->total_ios++;
275 eb->dev_bytenr = multi->stripes[0].physical;
276 kfree(multi);
277 multi = NULL;
278 } else {
279 /* special case for restore metadump */
280 list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
281 if (device->devid == 1)
282 break;
285 eb->fd = device->fd;
286 eb->dev_bytenr = eb->start;
287 device->total_ios++;
290 if (read_len > bytes_left)
291 read_len = bytes_left;
293 ret = read_extent_from_disk(eb, offset, read_len);
294 if (ret)
295 return -EIO;
296 offset += read_len;
297 bytes_left -= read_len;
299 return 0;
302 struct extent_buffer* read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
303 u64 parent_transid)
305 int ret;
306 struct extent_buffer *eb;
307 u64 best_transid = 0;
308 u32 sectorsize = fs_info->sectorsize;
309 int mirror_num = 0;
310 int good_mirror = 0;
311 int num_copies;
312 int ignore = 0;
315 * Don't even try to create tree block for unaligned tree block
316 * bytenr.
317 * Such unaligned tree block will free overlapping extent buffer,
318 * causing use-after-free bugs for fuzzed images.
320 if (bytenr < sectorsize || !IS_ALIGNED(bytenr, sectorsize)) {
321 error("tree block bytenr %llu is not aligned to sectorsize %u",
322 bytenr, sectorsize);
323 return ERR_PTR(-EIO);
326 eb = btrfs_find_create_tree_block(fs_info, bytenr);
327 if (!eb)
328 return ERR_PTR(-ENOMEM);
330 if (btrfs_buffer_uptodate(eb, parent_transid))
331 return eb;
333 while (1) {
334 ret = read_whole_eb(fs_info, eb, mirror_num);
335 if (ret == 0 && csum_tree_block(fs_info, eb, 1) == 0 &&
336 check_tree_block(fs_info, eb) == 0 &&
337 verify_parent_transid(eb->tree, eb, parent_transid, ignore)
338 == 0) {
339 if (eb->flags & EXTENT_BAD_TRANSID &&
340 list_empty(&eb->recow)) {
341 list_add_tail(&eb->recow,
342 &fs_info->recow_ebs);
343 eb->refs++;
345 btrfs_set_buffer_uptodate(eb);
346 return eb;
348 if (ignore) {
349 if (check_tree_block(fs_info, eb)) {
350 if (!fs_info->suppress_check_block_errors)
351 print_tree_block_error(fs_info, eb,
352 check_tree_block(fs_info, eb));
353 } else {
354 if (!fs_info->suppress_check_block_errors)
355 fprintf(stderr, "Csum didn't match\n");
357 ret = -EIO;
358 break;
360 num_copies = btrfs_num_copies(fs_info, eb->start, eb->len);
361 if (num_copies == 1) {
362 ignore = 1;
363 continue;
365 if (btrfs_header_generation(eb) > best_transid && mirror_num) {
366 best_transid = btrfs_header_generation(eb);
367 good_mirror = mirror_num;
369 mirror_num++;
370 if (mirror_num > num_copies) {
371 mirror_num = good_mirror;
372 ignore = 1;
373 continue;
376 free_extent_buffer(eb);
377 return ERR_PTR(ret);
380 int read_extent_data(struct btrfs_fs_info *fs_info, char *data, u64 logical,
381 u64 *len, int mirror)
383 u64 offset = 0;
384 struct btrfs_multi_bio *multi = NULL;
385 struct btrfs_device *device;
386 int ret = 0;
387 u64 max_len = *len;
389 ret = btrfs_map_block(fs_info, READ, logical, len, &multi, mirror,
390 NULL);
391 if (ret) {
392 fprintf(stderr, "Couldn't map the block %llu\n",
393 logical + offset);
394 goto err;
396 device = multi->stripes[0].dev;
398 if (*len > max_len)
399 *len = max_len;
400 if (device->fd < 0) {
401 ret = -EIO;
402 goto err;
405 ret = pread64(device->fd, data, *len, multi->stripes[0].physical);
406 if (ret != *len)
407 ret = -EIO;
408 else
409 ret = 0;
410 err:
411 kfree(multi);
412 return ret;
415 int write_and_map_eb(struct btrfs_fs_info *fs_info, struct extent_buffer *eb)
417 int ret;
418 int dev_nr;
419 u64 length;
420 u64 *raid_map = NULL;
421 struct btrfs_multi_bio *multi = NULL;
423 dev_nr = 0;
424 length = eb->len;
425 ret = btrfs_map_block(fs_info, WRITE, eb->start, &length,
426 &multi, 0, &raid_map);
428 if (raid_map) {
429 ret = write_raid56_with_parity(fs_info, eb, multi,
430 length, raid_map);
431 BUG_ON(ret);
432 } else while (dev_nr < multi->num_stripes) {
433 BUG_ON(ret);
434 eb->fd = multi->stripes[dev_nr].dev->fd;
435 eb->dev_bytenr = multi->stripes[dev_nr].physical;
436 multi->stripes[dev_nr].dev->total_ios++;
437 dev_nr++;
438 ret = write_extent_to_disk(eb);
439 BUG_ON(ret);
441 kfree(raid_map);
442 kfree(multi);
443 return 0;
446 int write_tree_block(struct btrfs_trans_handle *trans,
447 struct btrfs_fs_info *fs_info,
448 struct extent_buffer *eb)
450 if (check_tree_block(fs_info, eb)) {
451 print_tree_block_error(fs_info, eb,
452 check_tree_block(fs_info, eb));
453 BUG();
456 if (trans && !btrfs_buffer_uptodate(eb, trans->transid))
457 BUG();
459 btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
460 csum_tree_block(fs_info, eb, 0);
462 return write_and_map_eb(fs_info, eb);
465 void btrfs_setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
466 u64 objectid)
468 root->node = NULL;
469 root->commit_root = NULL;
470 root->ref_cows = 0;
471 root->track_dirty = 0;
473 root->fs_info = fs_info;
474 root->objectid = objectid;
475 root->last_trans = 0;
476 root->last_inode_alloc = 0;
478 INIT_LIST_HEAD(&root->dirty_list);
479 INIT_LIST_HEAD(&root->orphan_data_extents);
480 memset(&root->root_key, 0, sizeof(root->root_key));
481 memset(&root->root_item, 0, sizeof(root->root_item));
482 root->root_key.objectid = objectid;
485 static int find_and_setup_root(struct btrfs_root *tree_root,
486 struct btrfs_fs_info *fs_info,
487 u64 objectid, struct btrfs_root *root)
489 int ret;
490 u64 generation;
492 btrfs_setup_root(root, fs_info, objectid);
493 ret = btrfs_find_last_root(tree_root, objectid,
494 &root->root_item, &root->root_key);
495 if (ret)
496 return ret;
498 generation = btrfs_root_generation(&root->root_item);
499 root->node = read_tree_block(fs_info,
500 btrfs_root_bytenr(&root->root_item), generation);
501 if (!extent_buffer_uptodate(root->node))
502 return -EIO;
504 return 0;
507 static int find_and_setup_log_root(struct btrfs_root *tree_root,
508 struct btrfs_fs_info *fs_info,
509 struct btrfs_super_block *disk_super)
511 u64 blocknr = btrfs_super_log_root(disk_super);
512 struct btrfs_root *log_root = malloc(sizeof(struct btrfs_root));
514 if (!log_root)
515 return -ENOMEM;
517 if (blocknr == 0) {
518 free(log_root);
519 return 0;
522 btrfs_setup_root(log_root, fs_info,
523 BTRFS_TREE_LOG_OBJECTID);
525 log_root->node = read_tree_block(fs_info, blocknr,
526 btrfs_super_generation(disk_super) + 1);
528 fs_info->log_root_tree = log_root;
530 if (!extent_buffer_uptodate(log_root->node)) {
531 free_extent_buffer(log_root->node);
532 free(log_root);
533 fs_info->log_root_tree = NULL;
534 return -EIO;
537 return 0;
540 int btrfs_free_fs_root(struct btrfs_root *root)
542 if (root->node)
543 free_extent_buffer(root->node);
544 if (root->commit_root)
545 free_extent_buffer(root->commit_root);
546 kfree(root);
547 return 0;
550 static void __free_fs_root(struct rb_node *node)
552 struct btrfs_root *root;
554 root = container_of(node, struct btrfs_root, rb_node);
555 btrfs_free_fs_root(root);
558 FREE_RB_BASED_TREE(fs_roots, __free_fs_root);
560 struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
561 struct btrfs_key *location)
563 struct btrfs_root *root;
564 struct btrfs_root *tree_root = fs_info->tree_root;
565 struct btrfs_path *path;
566 struct extent_buffer *l;
567 u64 generation;
568 int ret = 0;
570 root = calloc(1, sizeof(*root));
571 if (!root)
572 return ERR_PTR(-ENOMEM);
573 if (location->offset == (u64)-1) {
574 ret = find_and_setup_root(tree_root, fs_info,
575 location->objectid, root);
576 if (ret) {
577 free(root);
578 return ERR_PTR(ret);
580 goto insert;
583 btrfs_setup_root(root, fs_info,
584 location->objectid);
586 path = btrfs_alloc_path();
587 if (!path) {
588 free(root);
589 return ERR_PTR(-ENOMEM);
592 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
593 if (ret != 0) {
594 if (ret > 0)
595 ret = -ENOENT;
596 goto out;
598 l = path->nodes[0];
599 read_extent_buffer(l, &root->root_item,
600 btrfs_item_ptr_offset(l, path->slots[0]),
601 sizeof(root->root_item));
602 memcpy(&root->root_key, location, sizeof(*location));
603 ret = 0;
604 out:
605 btrfs_free_path(path);
606 if (ret) {
607 free(root);
608 return ERR_PTR(ret);
610 generation = btrfs_root_generation(&root->root_item);
611 root->node = read_tree_block(fs_info,
612 btrfs_root_bytenr(&root->root_item), generation);
613 if (!extent_buffer_uptodate(root->node)) {
614 free(root);
615 return ERR_PTR(-EIO);
617 insert:
618 root->ref_cows = 1;
619 return root;
622 static int btrfs_fs_roots_compare_objectids(struct rb_node *node,
623 void *data)
625 u64 objectid = *((u64 *)data);
626 struct btrfs_root *root;
628 root = rb_entry(node, struct btrfs_root, rb_node);
629 if (objectid > root->objectid)
630 return 1;
631 else if (objectid < root->objectid)
632 return -1;
633 else
634 return 0;
637 static int btrfs_fs_roots_compare_roots(struct rb_node *node1,
638 struct rb_node *node2)
640 struct btrfs_root *root;
642 root = rb_entry(node2, struct btrfs_root, rb_node);
643 return btrfs_fs_roots_compare_objectids(node1, (void *)&root->objectid);
646 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
647 struct btrfs_key *location)
649 struct btrfs_root *root;
650 struct rb_node *node;
651 int ret;
652 u64 objectid = location->objectid;
654 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
655 return fs_info->tree_root;
656 if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
657 return fs_info->extent_root;
658 if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
659 return fs_info->chunk_root;
660 if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
661 return fs_info->dev_root;
662 if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
663 return fs_info->csum_root;
664 if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
665 return fs_info->quota_enabled ? fs_info->quota_root :
666 ERR_PTR(-ENOENT);
668 BUG_ON(location->objectid == BTRFS_TREE_RELOC_OBJECTID ||
669 location->offset != (u64)-1);
671 node = rb_search(&fs_info->fs_root_tree, (void *)&objectid,
672 btrfs_fs_roots_compare_objectids, NULL);
673 if (node)
674 return container_of(node, struct btrfs_root, rb_node);
676 root = btrfs_read_fs_root_no_cache(fs_info, location);
677 if (IS_ERR(root))
678 return root;
680 ret = rb_insert(&fs_info->fs_root_tree, &root->rb_node,
681 btrfs_fs_roots_compare_roots);
682 BUG_ON(ret);
683 return root;
686 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
688 if (fs_info->quota_root)
689 free(fs_info->quota_root);
691 free(fs_info->tree_root);
692 free(fs_info->extent_root);
693 free(fs_info->chunk_root);
694 free(fs_info->dev_root);
695 free(fs_info->csum_root);
696 free(fs_info->free_space_root);
697 free(fs_info->super_copy);
698 free(fs_info->log_root_tree);
699 free(fs_info);
702 struct btrfs_fs_info *btrfs_new_fs_info(int writable, u64 sb_bytenr)
704 struct btrfs_fs_info *fs_info;
706 fs_info = calloc(1, sizeof(struct btrfs_fs_info));
707 if (!fs_info)
708 return NULL;
710 fs_info->tree_root = calloc(1, sizeof(struct btrfs_root));
711 fs_info->extent_root = calloc(1, sizeof(struct btrfs_root));
712 fs_info->chunk_root = calloc(1, sizeof(struct btrfs_root));
713 fs_info->dev_root = calloc(1, sizeof(struct btrfs_root));
714 fs_info->csum_root = calloc(1, sizeof(struct btrfs_root));
715 fs_info->quota_root = calloc(1, sizeof(struct btrfs_root));
716 fs_info->free_space_root = calloc(1, sizeof(struct btrfs_root));
717 fs_info->super_copy = calloc(1, BTRFS_SUPER_INFO_SIZE);
719 if (!fs_info->tree_root || !fs_info->extent_root ||
720 !fs_info->chunk_root || !fs_info->dev_root ||
721 !fs_info->csum_root || !fs_info->quota_root ||
722 !fs_info->free_space_root || !fs_info->super_copy)
723 goto free_all;
725 extent_io_tree_init(&fs_info->extent_cache);
726 extent_io_tree_init(&fs_info->free_space_cache);
727 extent_io_tree_init(&fs_info->block_group_cache);
728 extent_io_tree_init(&fs_info->pinned_extents);
729 extent_io_tree_init(&fs_info->pending_del);
730 extent_io_tree_init(&fs_info->extent_ins);
731 fs_info->excluded_extents = NULL;
733 fs_info->fs_root_tree = RB_ROOT;
734 cache_tree_init(&fs_info->mapping_tree.cache_tree);
736 mutex_init(&fs_info->fs_mutex);
737 INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
738 INIT_LIST_HEAD(&fs_info->space_info);
739 INIT_LIST_HEAD(&fs_info->recow_ebs);
741 if (!writable)
742 fs_info->readonly = 1;
744 fs_info->super_bytenr = sb_bytenr;
745 fs_info->data_alloc_profile = (u64)-1;
746 fs_info->metadata_alloc_profile = (u64)-1;
747 fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
748 return fs_info;
749 free_all:
750 btrfs_free_fs_info(fs_info);
751 return NULL;
754 int btrfs_check_fs_compatibility(struct btrfs_super_block *sb,
755 unsigned int flags)
757 u64 features;
759 features = btrfs_super_incompat_flags(sb) &
760 ~BTRFS_FEATURE_INCOMPAT_SUPP;
761 if (features) {
762 printk("couldn't open because of unsupported "
763 "option features (%Lx).\n",
764 (unsigned long long)features);
765 return -ENOTSUP;
768 features = btrfs_super_incompat_flags(sb);
769 if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
770 features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
771 btrfs_set_super_incompat_flags(sb, features);
774 features = btrfs_super_compat_ro_flags(sb);
775 if (flags & OPEN_CTREE_WRITES) {
776 if (flags & OPEN_CTREE_INVALIDATE_FST) {
777 /* Clear the FREE_SPACE_TREE_VALID bit on disk... */
778 features &= ~BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID;
779 btrfs_set_super_compat_ro_flags(sb, features);
780 /* ... and ignore the free space tree bit. */
781 features &= ~BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE;
783 if (features & ~BTRFS_FEATURE_COMPAT_RO_SUPP) {
784 printk("couldn't open RDWR because of unsupported "
785 "option features (%Lx).\n",
786 (unsigned long long)features);
787 return -ENOTSUP;
791 return 0;
794 static int find_best_backup_root(struct btrfs_super_block *super)
796 struct btrfs_root_backup *backup;
797 u64 orig_gen = btrfs_super_generation(super);
798 u64 gen = 0;
799 int best_index = 0;
800 int i;
802 for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
803 backup = super->super_roots + i;
804 if (btrfs_backup_tree_root_gen(backup) != orig_gen &&
805 btrfs_backup_tree_root_gen(backup) > gen) {
806 best_index = i;
807 gen = btrfs_backup_tree_root_gen(backup);
810 return best_index;
813 static int setup_root_or_create_block(struct btrfs_fs_info *fs_info,
814 unsigned flags,
815 struct btrfs_root *info_root,
816 u64 objectid, char *str)
818 struct btrfs_root *root = fs_info->tree_root;
819 int ret;
821 ret = find_and_setup_root(root, fs_info, objectid, info_root);
822 if (ret) {
823 printk("Couldn't setup %s tree\n", str);
824 if (!(flags & OPEN_CTREE_PARTIAL))
825 return -EIO;
827 * Need a blank node here just so we don't screw up in the
828 * million of places that assume a root has a valid ->node
830 info_root->node =
831 btrfs_find_create_tree_block(fs_info, 0);
832 if (!info_root->node)
833 return -ENOMEM;
834 clear_extent_buffer_uptodate(info_root->node);
837 return 0;
840 int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info, u64 root_tree_bytenr,
841 unsigned flags)
843 struct btrfs_super_block *sb = fs_info->super_copy;
844 struct btrfs_root *root;
845 struct btrfs_key key;
846 u64 generation;
847 int ret;
849 root = fs_info->tree_root;
850 btrfs_setup_root(root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
851 generation = btrfs_super_generation(sb);
853 if (!root_tree_bytenr && !(flags & OPEN_CTREE_BACKUP_ROOT)) {
854 root_tree_bytenr = btrfs_super_root(sb);
855 } else if (flags & OPEN_CTREE_BACKUP_ROOT) {
856 struct btrfs_root_backup *backup;
857 int index = find_best_backup_root(sb);
858 if (index >= BTRFS_NUM_BACKUP_ROOTS) {
859 fprintf(stderr, "Invalid backup root number\n");
860 return -EIO;
862 backup = fs_info->super_copy->super_roots + index;
863 root_tree_bytenr = btrfs_backup_tree_root(backup);
864 generation = btrfs_backup_tree_root_gen(backup);
867 root->node = read_tree_block(fs_info, root_tree_bytenr, generation);
868 if (!extent_buffer_uptodate(root->node)) {
869 fprintf(stderr, "Couldn't read tree root\n");
870 return -EIO;
873 ret = setup_root_or_create_block(fs_info, flags, fs_info->extent_root,
874 BTRFS_EXTENT_TREE_OBJECTID, "extent");
875 if (ret)
876 return ret;
877 fs_info->extent_root->track_dirty = 1;
879 ret = find_and_setup_root(root, fs_info, BTRFS_DEV_TREE_OBJECTID,
880 fs_info->dev_root);
881 if (ret) {
882 printk("Couldn't setup device tree\n");
883 return -EIO;
885 fs_info->dev_root->track_dirty = 1;
887 ret = setup_root_or_create_block(fs_info, flags, fs_info->csum_root,
888 BTRFS_CSUM_TREE_OBJECTID, "csum");
889 if (ret)
890 return ret;
891 fs_info->csum_root->track_dirty = 1;
893 ret = find_and_setup_root(root, fs_info, BTRFS_QUOTA_TREE_OBJECTID,
894 fs_info->quota_root);
895 if (ret) {
896 free(fs_info->quota_root);
897 fs_info->quota_root = NULL;
898 } else {
899 fs_info->quota_enabled = 1;
902 if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
903 ret = find_and_setup_root(root, fs_info, BTRFS_FREE_SPACE_TREE_OBJECTID,
904 fs_info->free_space_root);
905 if (ret) {
906 printk("Couldn't read free space tree\n");
907 return -EIO;
909 fs_info->free_space_root->track_dirty = 1;
912 ret = find_and_setup_log_root(root, fs_info, sb);
913 if (ret) {
914 printk("Couldn't setup log root tree\n");
915 if (!(flags & OPEN_CTREE_PARTIAL))
916 return -EIO;
919 fs_info->generation = generation;
920 fs_info->last_trans_committed = generation;
921 if (extent_buffer_uptodate(fs_info->extent_root->node) &&
922 !(flags & OPEN_CTREE_NO_BLOCK_GROUPS)) {
923 ret = btrfs_read_block_groups(fs_info->tree_root);
925 * If we don't find any blockgroups (ENOENT) we're either
926 * restoring or creating the filesystem, where it's expected,
927 * anything else is error
929 if (ret != -ENOENT)
930 return -EIO;
933 key.objectid = BTRFS_FS_TREE_OBJECTID;
934 key.type = BTRFS_ROOT_ITEM_KEY;
935 key.offset = (u64)-1;
936 fs_info->fs_root = btrfs_read_fs_root(fs_info, &key);
938 if (IS_ERR(fs_info->fs_root))
939 return -EIO;
940 return 0;
943 void btrfs_release_all_roots(struct btrfs_fs_info *fs_info)
945 if (fs_info->free_space_root)
946 free_extent_buffer(fs_info->free_space_root->node);
947 if (fs_info->quota_root)
948 free_extent_buffer(fs_info->quota_root->node);
949 if (fs_info->csum_root)
950 free_extent_buffer(fs_info->csum_root->node);
951 if (fs_info->dev_root)
952 free_extent_buffer(fs_info->dev_root->node);
953 if (fs_info->extent_root)
954 free_extent_buffer(fs_info->extent_root->node);
955 if (fs_info->tree_root)
956 free_extent_buffer(fs_info->tree_root->node);
957 if (fs_info->log_root_tree)
958 free_extent_buffer(fs_info->log_root_tree->node);
959 if (fs_info->chunk_root)
960 free_extent_buffer(fs_info->chunk_root->node);
963 static void free_map_lookup(struct cache_extent *ce)
965 struct map_lookup *map;
967 map = container_of(ce, struct map_lookup, ce);
968 kfree(map);
971 FREE_EXTENT_CACHE_BASED_TREE(mapping_cache, free_map_lookup);
973 void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info)
975 while (!list_empty(&fs_info->recow_ebs)) {
976 struct extent_buffer *eb;
977 eb = list_first_entry(&fs_info->recow_ebs,
978 struct extent_buffer, recow);
979 list_del_init(&eb->recow);
980 free_extent_buffer(eb);
982 free_mapping_cache_tree(&fs_info->mapping_tree.cache_tree);
983 extent_io_tree_cleanup(&fs_info->extent_cache);
984 extent_io_tree_cleanup(&fs_info->free_space_cache);
985 extent_io_tree_cleanup(&fs_info->block_group_cache);
986 extent_io_tree_cleanup(&fs_info->pinned_extents);
987 extent_io_tree_cleanup(&fs_info->pending_del);
988 extent_io_tree_cleanup(&fs_info->extent_ins);
991 int btrfs_scan_fs_devices(int fd, const char *path,
992 struct btrfs_fs_devices **fs_devices,
993 u64 sb_bytenr, unsigned sbflags,
994 int skip_devices)
996 u64 total_devs;
997 u64 dev_size;
998 off_t seek_ret;
999 int ret;
1000 if (!sb_bytenr)
1001 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
1003 seek_ret = lseek(fd, 0, SEEK_END);
1004 if (seek_ret < 0)
1005 return -errno;
1007 dev_size = seek_ret;
1008 lseek(fd, 0, SEEK_SET);
1009 if (sb_bytenr > dev_size) {
1010 error("superblock bytenr %llu is larger than device size %llu",
1011 (unsigned long long)sb_bytenr,
1012 (unsigned long long)dev_size);
1013 return -EINVAL;
1016 ret = btrfs_scan_one_device(fd, path, fs_devices,
1017 &total_devs, sb_bytenr, sbflags);
1018 if (ret) {
1019 fprintf(stderr, "No valid Btrfs found on %s\n", path);
1020 return ret;
1023 if (!skip_devices && total_devs != 1) {
1024 ret = btrfs_scan_devices();
1025 if (ret)
1026 return ret;
1028 return 0;
1031 int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info,
1032 u64 chunk_root_bytenr)
1034 struct btrfs_super_block *sb = fs_info->super_copy;
1035 u64 generation;
1036 int ret;
1038 btrfs_setup_root(fs_info->chunk_root, fs_info,
1039 BTRFS_CHUNK_TREE_OBJECTID);
1041 ret = btrfs_read_sys_array(fs_info);
1042 if (ret)
1043 return ret;
1045 generation = btrfs_super_chunk_root_generation(sb);
1047 if (chunk_root_bytenr && !IS_ALIGNED(chunk_root_bytenr,
1048 fs_info->sectorsize)) {
1049 warning("chunk_root_bytenr %llu is unaligned to %u, ignore it",
1050 chunk_root_bytenr, fs_info->sectorsize);
1051 chunk_root_bytenr = 0;
1054 if (!chunk_root_bytenr)
1055 chunk_root_bytenr = btrfs_super_chunk_root(sb);
1056 else
1057 generation = 0;
1059 fs_info->chunk_root->node = read_tree_block(fs_info,
1060 chunk_root_bytenr,
1061 generation);
1062 if (!extent_buffer_uptodate(fs_info->chunk_root->node)) {
1063 if (fs_info->ignore_chunk_tree_error) {
1064 warning("cannot read chunk root, continue anyway");
1065 fs_info->chunk_root = NULL;
1066 return 0;
1067 } else {
1068 error("cannot read chunk root");
1069 return -EIO;
1073 if (!(btrfs_super_flags(sb) & BTRFS_SUPER_FLAG_METADUMP)) {
1074 ret = btrfs_read_chunk_tree(fs_info);
1075 if (ret) {
1076 fprintf(stderr, "Couldn't read chunk tree\n");
1077 return ret;
1080 return 0;
1083 static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
1084 u64 sb_bytenr,
1085 u64 root_tree_bytenr,
1086 u64 chunk_root_bytenr,
1087 unsigned flags)
1089 struct btrfs_fs_info *fs_info;
1090 struct btrfs_super_block *disk_super;
1091 struct btrfs_fs_devices *fs_devices = NULL;
1092 struct extent_buffer *eb;
1093 int ret;
1094 int oflags;
1095 unsigned sbflags = SBREAD_DEFAULT;
1097 if (sb_bytenr == 0)
1098 sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
1100 /* try to drop all the caches */
1101 if (posix_fadvise(fp, 0, 0, POSIX_FADV_DONTNEED))
1102 fprintf(stderr, "Warning, could not drop caches\n");
1104 fs_info = btrfs_new_fs_info(flags & OPEN_CTREE_WRITES, sb_bytenr);
1105 if (!fs_info) {
1106 fprintf(stderr, "Failed to allocate memory for fs_info\n");
1107 return NULL;
1109 if (flags & OPEN_CTREE_RESTORE)
1110 fs_info->on_restoring = 1;
1111 if (flags & OPEN_CTREE_SUPPRESS_CHECK_BLOCK_ERRORS)
1112 fs_info->suppress_check_block_errors = 1;
1113 if (flags & OPEN_CTREE_IGNORE_FSID_MISMATCH)
1114 fs_info->ignore_fsid_mismatch = 1;
1115 if (flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR)
1116 fs_info->ignore_chunk_tree_error = 1;
1118 if ((flags & OPEN_CTREE_RECOVER_SUPER)
1119 && (flags & OPEN_CTREE_TEMPORARY_SUPER)) {
1120 fprintf(stderr,
1121 "cannot open a filesystem with temporary super block for recovery");
1122 goto out;
1125 if (flags & OPEN_CTREE_TEMPORARY_SUPER)
1126 sbflags = SBREAD_TEMPORARY;
1128 ret = btrfs_scan_fs_devices(fp, path, &fs_devices, sb_bytenr, sbflags,
1129 (flags & OPEN_CTREE_NO_DEVICES));
1130 if (ret)
1131 goto out;
1133 fs_info->fs_devices = fs_devices;
1134 if (flags & OPEN_CTREE_WRITES)
1135 oflags = O_RDWR;
1136 else
1137 oflags = O_RDONLY;
1139 if (flags & OPEN_CTREE_EXCLUSIVE)
1140 oflags |= O_EXCL;
1142 ret = btrfs_open_devices(fs_devices, oflags);
1143 if (ret)
1144 goto out;
1146 disk_super = fs_info->super_copy;
1147 if (flags & OPEN_CTREE_RECOVER_SUPER)
1148 ret = btrfs_read_dev_super(fs_devices->latest_bdev, disk_super,
1149 sb_bytenr, SBREAD_RECOVER);
1150 else
1151 ret = btrfs_read_dev_super(fp, disk_super, sb_bytenr,
1152 sbflags);
1153 if (ret) {
1154 printk("No valid btrfs found\n");
1155 goto out_devices;
1158 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID &&
1159 !fs_info->ignore_fsid_mismatch) {
1160 fprintf(stderr, "ERROR: Filesystem UUID change in progress\n");
1161 goto out_devices;
1164 memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
1165 fs_info->sectorsize = btrfs_super_sectorsize(disk_super);
1166 fs_info->nodesize = btrfs_super_nodesize(disk_super);
1167 fs_info->stripesize = btrfs_super_stripesize(disk_super);
1169 ret = btrfs_check_fs_compatibility(fs_info->super_copy, flags);
1170 if (ret)
1171 goto out_devices;
1173 ret = btrfs_setup_chunk_tree_and_device_map(fs_info, chunk_root_bytenr);
1174 if (ret)
1175 goto out_chunk;
1177 /* Chunk tree root is unable to read, return directly */
1178 if (!fs_info->chunk_root)
1179 return fs_info;
1181 eb = fs_info->chunk_root->node;
1182 read_extent_buffer(eb, fs_info->chunk_tree_uuid,
1183 btrfs_header_chunk_tree_uuid(eb),
1184 BTRFS_UUID_SIZE);
1186 ret = btrfs_setup_all_roots(fs_info, root_tree_bytenr, flags);
1187 if (ret && !(flags & __OPEN_CTREE_RETURN_CHUNK_ROOT) &&
1188 !fs_info->ignore_chunk_tree_error)
1189 goto out_chunk;
1191 return fs_info;
1193 out_chunk:
1194 btrfs_release_all_roots(fs_info);
1195 btrfs_cleanup_all_caches(fs_info);
1196 out_devices:
1197 btrfs_close_devices(fs_devices);
1198 out:
1199 btrfs_free_fs_info(fs_info);
1200 return NULL;
1203 struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
1204 u64 sb_bytenr, u64 root_tree_bytenr,
1205 u64 chunk_root_bytenr,
1206 unsigned flags)
1208 int fp;
1209 int ret;
1210 struct btrfs_fs_info *info;
1211 int oflags = O_RDWR;
1212 struct stat st;
1214 ret = stat(filename, &st);
1215 if (ret < 0) {
1216 error("cannot stat '%s': %m", filename);
1217 return NULL;
1219 if (!(((st.st_mode & S_IFMT) == S_IFREG) || ((st.st_mode & S_IFMT) == S_IFBLK))) {
1220 error("not a regular file or block device: %s", filename);
1221 return NULL;
1224 if (!(flags & OPEN_CTREE_WRITES))
1225 oflags = O_RDONLY;
1227 fp = open(filename, oflags);
1228 if (fp < 0) {
1229 error("cannot open '%s': %m", filename);
1230 return NULL;
1232 info = __open_ctree_fd(fp, filename, sb_bytenr, root_tree_bytenr,
1233 chunk_root_bytenr, flags);
1234 close(fp);
1235 return info;
1238 struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr,
1239 unsigned flags)
1241 struct btrfs_fs_info *info;
1243 /* This flags may not return fs_info with any valid root */
1244 BUG_ON(flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR);
1245 info = open_ctree_fs_info(filename, sb_bytenr, 0, 0, flags);
1246 if (!info)
1247 return NULL;
1248 if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
1249 return info->chunk_root;
1250 return info->fs_root;
1253 struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
1254 unsigned flags)
1256 struct btrfs_fs_info *info;
1258 /* This flags may not return fs_info with any valid root */
1259 if (flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR) {
1260 error("invalid open_ctree flags: 0x%llx",
1261 (unsigned long long)flags);
1262 return NULL;
1264 info = __open_ctree_fd(fp, path, sb_bytenr, 0, 0, flags);
1265 if (!info)
1266 return NULL;
1267 if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
1268 return info->chunk_root;
1269 return info->fs_root;
1273 * Check if the super is valid:
1274 * - nodesize/sectorsize - minimum, maximum, alignment
1275 * - tree block starts - alignment
1276 * - number of devices - something sane
1277 * - sys array size - maximum
1279 static int check_super(struct btrfs_super_block *sb, unsigned sbflags)
1281 u8 result[BTRFS_CSUM_SIZE];
1282 u32 crc;
1283 u16 csum_type;
1284 int csum_size;
1286 if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
1287 if (btrfs_super_magic(sb) == BTRFS_MAGIC_TEMPORARY) {
1288 if (!(sbflags & SBREAD_TEMPORARY)) {
1289 error("superblock magic doesn't match");
1290 return -EIO;
1295 csum_type = btrfs_super_csum_type(sb);
1296 if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) {
1297 error("unsupported checksum algorithm %u", csum_type);
1298 return -EIO;
1300 csum_size = btrfs_csum_sizes[csum_type];
1302 crc = ~(u32)0;
1303 crc = btrfs_csum_data((char *)sb + BTRFS_CSUM_SIZE, crc,
1304 BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1305 btrfs_csum_final(crc, result);
1307 if (memcmp(result, sb->csum, csum_size)) {
1308 error("superblock checksum mismatch");
1309 return -EIO;
1311 if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
1312 error("tree_root level too big: %d >= %d",
1313 btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
1314 goto error_out;
1316 if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
1317 error("chunk_root level too big: %d >= %d",
1318 btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
1319 goto error_out;
1321 if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
1322 error("log_root level too big: %d >= %d",
1323 btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
1324 goto error_out;
1327 if (!IS_ALIGNED(btrfs_super_root(sb), 4096)) {
1328 error("tree_root block unaligned: %llu", btrfs_super_root(sb));
1329 goto error_out;
1331 if (!IS_ALIGNED(btrfs_super_chunk_root(sb), 4096)) {
1332 error("chunk_root block unaligned: %llu",
1333 btrfs_super_chunk_root(sb));
1334 goto error_out;
1336 if (!IS_ALIGNED(btrfs_super_log_root(sb), 4096)) {
1337 error("log_root block unaligned: %llu",
1338 btrfs_super_log_root(sb));
1339 goto error_out;
1341 if (btrfs_super_nodesize(sb) < 4096) {
1342 error("nodesize too small: %u < 4096",
1343 btrfs_super_nodesize(sb));
1344 goto error_out;
1346 if (!IS_ALIGNED(btrfs_super_nodesize(sb), 4096)) {
1347 error("nodesize unaligned: %u", btrfs_super_nodesize(sb));
1348 goto error_out;
1350 if (btrfs_super_sectorsize(sb) < 4096) {
1351 error("sectorsize too small: %u < 4096",
1352 btrfs_super_sectorsize(sb));
1353 goto error_out;
1355 if (!IS_ALIGNED(btrfs_super_sectorsize(sb), 4096)) {
1356 error("sectorsize unaligned: %u", btrfs_super_sectorsize(sb));
1357 goto error_out;
1359 if (btrfs_super_total_bytes(sb) == 0) {
1360 error("invalid total_bytes 0");
1361 goto error_out;
1363 if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
1364 error("invalid bytes_used %llu", btrfs_super_bytes_used(sb));
1365 goto error_out;
1367 if ((btrfs_super_stripesize(sb) != 4096)
1368 && (btrfs_super_stripesize(sb) != btrfs_super_sectorsize(sb))) {
1369 error("invalid stripesize %u", btrfs_super_stripesize(sb));
1370 goto error_out;
1373 if (memcmp(sb->fsid, sb->dev_item.fsid, BTRFS_UUID_SIZE) != 0) {
1374 char fsid[BTRFS_UUID_UNPARSED_SIZE];
1375 char dev_fsid[BTRFS_UUID_UNPARSED_SIZE];
1377 uuid_unparse(sb->fsid, fsid);
1378 uuid_unparse(sb->dev_item.fsid, dev_fsid);
1379 error("dev_item UUID does not match fsid: %s != %s",
1380 dev_fsid, fsid);
1381 goto error_out;
1385 * Hint to catch really bogus numbers, bitflips or so
1387 if (btrfs_super_num_devices(sb) > (1UL << 31)) {
1388 warning("suspicious number of devices: %llu",
1389 btrfs_super_num_devices(sb));
1392 if (btrfs_super_num_devices(sb) == 0) {
1393 error("number of devices is 0");
1394 goto error_out;
1398 * Obvious sys_chunk_array corruptions, it must hold at least one key
1399 * and one chunk
1401 if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
1402 error("system chunk array too big %u > %u",
1403 btrfs_super_sys_array_size(sb),
1404 BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
1405 goto error_out;
1407 if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
1408 + sizeof(struct btrfs_chunk)) {
1409 error("system chunk array too small %u < %zu",
1410 btrfs_super_sys_array_size(sb),
1411 sizeof(struct btrfs_disk_key) +
1412 sizeof(struct btrfs_chunk));
1413 goto error_out;
1416 return 0;
1418 error_out:
1419 error("superblock checksum matches but it has invalid members");
1420 return -EIO;
1424 * btrfs_read_dev_super - read a valid superblock from a block device
1425 * @fd: file descriptor of the device
1426 * @sb: buffer where the superblock is going to be read in
1427 * @sb_bytenr: offset of the particular superblock copy we want
1428 * @sbflags: flags controlling how the superblock is read
1430 * This function is used by various btrfs comands to obtain a valid superblock.
1432 * It's mode of operation is controlled by the @sb_bytenr and @sbdflags
1433 * parameters. If SBREAD_RECOVER flag is set and @sb_bytenr is
1434 * BTRFS_SUPER_INFO_OFFSET then the function reads all 3 superblock copies and
1435 * returns the newest one. If SBREAD_RECOVER is not set then only a single
1436 * copy is read, which one is decided by @sb_bytenr. If @sb_bytenr !=
1437 * BTRFS_SUPER_INFO_OFFSET then the @sbflags is effectively ignored and only a
1438 * single copy is read.
1440 int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr,
1441 unsigned sbflags)
1443 u8 fsid[BTRFS_FSID_SIZE];
1444 int fsid_is_initialized = 0;
1445 char tmp[BTRFS_SUPER_INFO_SIZE];
1446 struct btrfs_super_block *buf = (struct btrfs_super_block *)tmp;
1447 int i;
1448 int ret;
1449 int max_super = sbflags & SBREAD_RECOVER ? BTRFS_SUPER_MIRROR_MAX : 1;
1450 u64 transid = 0;
1451 u64 bytenr;
1453 if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) {
1454 ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
1455 /* real error */
1456 if (ret < 0)
1457 return -errno;
1459 /* Not large enough sb, return -ENOENT instead of normal -EIO */
1460 if (ret < BTRFS_SUPER_INFO_SIZE)
1461 return -ENOENT;
1463 if (btrfs_super_bytenr(buf) != sb_bytenr)
1464 return -EIO;
1466 ret = check_super(buf, sbflags);
1467 if (ret < 0)
1468 return ret;
1469 memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE);
1470 return 0;
1474 * we would like to check all the supers, but that would make
1475 * a btrfs mount succeed after a mkfs from a different FS.
1476 * So, we need to add a special mount option to scan for
1477 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
1480 for (i = 0; i < max_super; i++) {
1481 bytenr = btrfs_sb_offset(i);
1482 ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, bytenr);
1483 if (ret < BTRFS_SUPER_INFO_SIZE)
1484 break;
1486 if (btrfs_super_bytenr(buf) != bytenr )
1487 continue;
1488 /* if magic is NULL, the device was removed */
1489 if (btrfs_super_magic(buf) == 0 && i == 0)
1490 break;
1491 if (check_super(buf, sbflags))
1492 continue;
1494 if (!fsid_is_initialized) {
1495 memcpy(fsid, buf->fsid, sizeof(fsid));
1496 fsid_is_initialized = 1;
1497 } else if (memcmp(fsid, buf->fsid, sizeof(fsid))) {
1499 * the superblocks (the original one and
1500 * its backups) contain data of different
1501 * filesystems -> the super cannot be trusted
1503 continue;
1506 if (btrfs_super_generation(buf) > transid) {
1507 memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE);
1508 transid = btrfs_super_generation(buf);
1512 return transid > 0 ? 0 : -1;
1515 static int write_dev_supers(struct btrfs_fs_info *fs_info,
1516 struct btrfs_super_block *sb,
1517 struct btrfs_device *device)
1519 u64 bytenr;
1520 u32 crc;
1521 int i, ret;
1523 if (fs_info->super_bytenr != BTRFS_SUPER_INFO_OFFSET) {
1524 btrfs_set_super_bytenr(sb, fs_info->super_bytenr);
1525 crc = ~(u32)0;
1526 crc = btrfs_csum_data((char *)sb + BTRFS_CSUM_SIZE, crc,
1527 BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1528 btrfs_csum_final(crc, &sb->csum[0]);
1531 * super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
1532 * zero filled, we can use it directly
1534 ret = pwrite64(device->fd, fs_info->super_copy,
1535 BTRFS_SUPER_INFO_SIZE,
1536 fs_info->super_bytenr);
1537 if (ret != BTRFS_SUPER_INFO_SIZE)
1538 goto write_err;
1539 return 0;
1542 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1543 bytenr = btrfs_sb_offset(i);
1544 if (bytenr + BTRFS_SUPER_INFO_SIZE > device->total_bytes)
1545 break;
1547 btrfs_set_super_bytenr(sb, bytenr);
1549 crc = ~(u32)0;
1550 crc = btrfs_csum_data((char *)sb + BTRFS_CSUM_SIZE, crc,
1551 BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
1552 btrfs_csum_final(crc, &sb->csum[0]);
1555 * super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
1556 * zero filled, we can use it directly
1558 ret = pwrite64(device->fd, fs_info->super_copy,
1559 BTRFS_SUPER_INFO_SIZE, bytenr);
1560 if (ret != BTRFS_SUPER_INFO_SIZE)
1561 goto write_err;
1564 return 0;
1566 write_err:
1567 if (ret > 0)
1568 fprintf(stderr, "WARNING: failed to write all sb data\n");
1569 else
1570 fprintf(stderr, "WARNING: failed to write sb: %m\n");
1571 return ret;
1574 int write_all_supers(struct btrfs_fs_info *fs_info)
1576 struct list_head *head = &fs_info->fs_devices->devices;
1577 struct btrfs_device *dev;
1578 struct btrfs_super_block *sb;
1579 struct btrfs_dev_item *dev_item;
1580 int ret;
1581 u64 flags;
1583 sb = fs_info->super_copy;
1584 dev_item = &sb->dev_item;
1585 list_for_each_entry(dev, head, dev_list) {
1586 if (!dev->writeable)
1587 continue;
1589 btrfs_set_stack_device_generation(dev_item, 0);
1590 btrfs_set_stack_device_type(dev_item, dev->type);
1591 btrfs_set_stack_device_id(dev_item, dev->devid);
1592 btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
1593 btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
1594 btrfs_set_stack_device_io_align(dev_item, dev->io_align);
1595 btrfs_set_stack_device_io_width(dev_item, dev->io_width);
1596 btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
1597 memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
1598 memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
1600 flags = btrfs_super_flags(sb);
1601 btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
1603 ret = write_dev_supers(fs_info, sb, dev);
1604 BUG_ON(ret);
1606 return 0;
1609 int write_ctree_super(struct btrfs_trans_handle *trans,
1610 struct btrfs_fs_info *fs_info)
1612 int ret;
1613 struct btrfs_root *tree_root = fs_info->tree_root;
1614 struct btrfs_root *chunk_root = fs_info->chunk_root;
1616 if (fs_info->readonly)
1617 return 0;
1619 btrfs_set_super_generation(fs_info->super_copy,
1620 trans->transid);
1621 btrfs_set_super_root(fs_info->super_copy,
1622 tree_root->node->start);
1623 btrfs_set_super_root_level(fs_info->super_copy,
1624 btrfs_header_level(tree_root->node));
1625 btrfs_set_super_chunk_root(fs_info->super_copy,
1626 chunk_root->node->start);
1627 btrfs_set_super_chunk_root_level(fs_info->super_copy,
1628 btrfs_header_level(chunk_root->node));
1629 btrfs_set_super_chunk_root_generation(fs_info->super_copy,
1630 btrfs_header_generation(chunk_root->node));
1632 ret = write_all_supers(fs_info);
1633 if (ret)
1634 fprintf(stderr, "failed to write new super block err %d\n", ret);
1635 return ret;
1638 int close_ctree_fs_info(struct btrfs_fs_info *fs_info)
1640 int ret;
1641 int err = 0;
1642 struct btrfs_trans_handle *trans;
1643 struct btrfs_root *root = fs_info->tree_root;
1645 if (fs_info->last_trans_committed !=
1646 fs_info->generation) {
1647 BUG_ON(!root);
1648 trans = btrfs_start_transaction(root, 1);
1649 if (IS_ERR(trans)) {
1650 err = PTR_ERR(trans);
1651 goto skip_commit;
1653 btrfs_commit_transaction(trans, root);
1654 trans = btrfs_start_transaction(root, 1);
1655 BUG_ON(IS_ERR(trans));
1656 ret = commit_tree_roots(trans, fs_info);
1657 BUG_ON(ret);
1658 ret = __commit_transaction(trans, root);
1659 BUG_ON(ret);
1660 write_ctree_super(trans, fs_info);
1661 kfree(trans);
1664 if (fs_info->finalize_on_close) {
1665 btrfs_set_super_magic(fs_info->super_copy, BTRFS_MAGIC);
1666 root->fs_info->finalize_on_close = 0;
1667 ret = write_all_supers(fs_info);
1668 if (ret)
1669 fprintf(stderr,
1670 "failed to write new super block err %d\n", ret);
1673 skip_commit:
1674 btrfs_free_block_groups(fs_info);
1676 free_fs_roots_tree(&fs_info->fs_root_tree);
1678 btrfs_release_all_roots(fs_info);
1679 ret = btrfs_close_devices(fs_info->fs_devices);
1680 btrfs_cleanup_all_caches(fs_info);
1681 btrfs_free_fs_info(fs_info);
1682 if (!err)
1683 err = ret;
1684 return err;
1687 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
1688 struct extent_buffer *eb)
1690 return clear_extent_buffer_dirty(eb);
1693 void btrfs_mark_buffer_dirty(struct extent_buffer *eb)
1695 set_extent_buffer_dirty(eb);
1698 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
1700 int ret;
1702 ret = extent_buffer_uptodate(buf);
1703 if (!ret)
1704 return ret;
1706 ret = verify_parent_transid(buf->tree, buf, parent_transid, 1);
1707 return !ret;
1710 int btrfs_set_buffer_uptodate(struct extent_buffer *eb)
1712 return set_extent_buffer_uptodate(eb);