btrfs-progs/kernel-shared/disk-io.c
Dāvis Mosāns a2ccf96d76 btrfs-progs: fix checksum output for "checksum verify failed"
Currently only single checksum byte is printed.  Fix it so that
the whole checksum is printed, in the order as the bytes are stored in
the buffer. This matches what kernel does, though it might not
correspond to the cases of CRC32C and XXHASH as if they were stored in
integer variable and printed in the native format. For consistency we
need to print the same format.

Signed-off-by: Dāvis Mosāns <davispuh@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-03-15 14:59:40 +01:00

2059 lines
55 KiB
C

/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <uuid/uuid.h>
#include "kerncompat.h"
#include "kernel-lib/radix-tree.h"
#include "kernel-shared/ctree.h"
#include "kernel-shared/disk-io.h"
#include "kernel-shared/volumes.h"
#include "kernel-shared/transaction.h"
#include "crypto/crc32c.h"
#include "common/utils.h"
#include "kernel-shared/print-tree.h"
#include "common/rbtree-utils.h"
#include "common/device-scan.h"
#include "crypto/hash.h"
/* specified errno for check_tree_block */
#define BTRFS_BAD_BYTENR (-1)
#define BTRFS_BAD_FSID (-2)
#define BTRFS_BAD_LEVEL (-3)
#define BTRFS_BAD_NRITEMS (-4)
/* Calculate max possible nritems for a leaf/node */
static u32 max_nritems(u8 level, u32 nodesize)
{
if (level == 0)
return ((nodesize - sizeof(struct btrfs_header)) /
sizeof(struct btrfs_item));
return ((nodesize - sizeof(struct btrfs_header)) /
sizeof(struct btrfs_key_ptr));
}
static int check_tree_block(struct btrfs_fs_info *fs_info,
struct extent_buffer *buf)
{
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
u32 nodesize = fs_info->nodesize;
bool fsid_match = false;
int ret = BTRFS_BAD_FSID;
if (buf->start != btrfs_header_bytenr(buf))
return BTRFS_BAD_BYTENR;
if (btrfs_header_level(buf) >= BTRFS_MAX_LEVEL)
return BTRFS_BAD_LEVEL;
if (btrfs_header_nritems(buf) > max_nritems(btrfs_header_level(buf),
nodesize))
return BTRFS_BAD_NRITEMS;
/* Only leaf can be empty */
if (btrfs_header_nritems(buf) == 0 &&
btrfs_header_level(buf) != 0)
return BTRFS_BAD_NRITEMS;
while (fs_devices) {
/*
* Checking the incompat flag is only valid for the current
* fs. For seed devices it's forbidden to have their uuid
* changed so reading ->fsid in this case is fine
*/
if (fs_devices == fs_info->fs_devices &&
btrfs_fs_incompat(fs_info, METADATA_UUID))
fsid_match = !memcmp_extent_buffer(buf,
fs_devices->metadata_uuid,
btrfs_header_fsid(),
BTRFS_FSID_SIZE);
else
fsid_match = !memcmp_extent_buffer(buf,
fs_devices->fsid,
btrfs_header_fsid(),
BTRFS_FSID_SIZE);
if (fs_info->ignore_fsid_mismatch || fsid_match) {
ret = 0;
break;
}
fs_devices = fs_devices->seed;
}
return ret;
}
static void print_tree_block_error(struct btrfs_fs_info *fs_info,
struct extent_buffer *eb,
int err)
{
char fs_uuid[BTRFS_UUID_UNPARSED_SIZE] = {'\0'};
char found_uuid[BTRFS_UUID_UNPARSED_SIZE] = {'\0'};
u8 buf[BTRFS_UUID_SIZE];
if (!err)
return;
fprintf(stderr, "bad tree block %llu, ", eb->start);
switch (err) {
case BTRFS_BAD_FSID:
read_extent_buffer(eb, buf, btrfs_header_fsid(),
BTRFS_UUID_SIZE);
uuid_unparse(buf, found_uuid);
uuid_unparse(fs_info->fs_devices->metadata_uuid, fs_uuid);
fprintf(stderr, "fsid mismatch, want=%s, have=%s\n",
fs_uuid, found_uuid);
break;
case BTRFS_BAD_BYTENR:
fprintf(stderr, "bytenr mismatch, want=%llu, have=%llu\n",
eb->start, btrfs_header_bytenr(eb));
break;
case BTRFS_BAD_LEVEL:
fprintf(stderr, "bad level, %u > %d\n",
btrfs_header_level(eb), BTRFS_MAX_LEVEL);
break;
case BTRFS_BAD_NRITEMS:
fprintf(stderr, "invalid nr_items: %u\n",
btrfs_header_nritems(eb));
break;
}
}
int btrfs_csum_data(u16 csum_type, const u8 *data, u8 *out, size_t len)
{
memset(out, 0, BTRFS_CSUM_SIZE);
switch (csum_type) {
case BTRFS_CSUM_TYPE_CRC32:
return hash_crc32c(data, len, out);
case BTRFS_CSUM_TYPE_XXHASH:
return hash_xxhash(data, len, out);
case BTRFS_CSUM_TYPE_SHA256:
return hash_sha256(data, len, out);
case BTRFS_CSUM_TYPE_BLAKE2:
return hash_blake2b(data, len, out);
default:
fprintf(stderr, "ERROR: unknown csum type: %d\n", csum_type);
ASSERT(0);
}
return -1;
}
int btrfs_format_csum(u16 csum_type, const u8 *data, char *output)
{
int i;
const int csum_size = btrfs_csum_type_size(csum_type);
sprintf(output, "0x");
for (i = 0; i < csum_size; i++) {
output += 2;
sprintf(output, "%02x", data[i]);
}
return csum_size;
}
static int __csum_tree_block_size(struct extent_buffer *buf, u16 csum_size,
int verify, int silent, u16 csum_type)
{
u8 result[BTRFS_CSUM_SIZE];
u32 len;
len = buf->len - BTRFS_CSUM_SIZE;
btrfs_csum_data(csum_type, (u8 *)buf->data + BTRFS_CSUM_SIZE,
result, len);
if (verify) {
if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
if (!silent) {
/* "0x" plus 2 hex chars for each byte plus nul */
char found[2 + BTRFS_CSUM_SIZE * 2 + 1];
char wanted[2 + BTRFS_CSUM_SIZE * 2 + 1];
btrfs_format_csum(csum_type, result, found);
btrfs_format_csum(csum_type, (u8 *)buf->data, wanted);
printk(
"checksum verify failed on %llu wanted %s found %s\n",
(unsigned long long)buf->start,
wanted, found);
}
return 1;
}
} else {
write_extent_buffer(buf, result, 0, csum_size);
}
return 0;
}
int csum_tree_block_size(struct extent_buffer *buf, u16 csum_size, int verify,
u16 csum_type)
{
return __csum_tree_block_size(buf, csum_size, verify, 0, csum_type);
}
int verify_tree_block_csum_silent(struct extent_buffer *buf, u16 csum_size,
u16 csum_type)
{
return __csum_tree_block_size(buf, csum_size, 1, 1, csum_type);
}
int csum_tree_block(struct btrfs_fs_info *fs_info,
struct extent_buffer *buf, int verify)
{
u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
u16 csum_type = btrfs_super_csum_type(fs_info->super_copy);
if (verify && fs_info->suppress_check_block_errors)
return verify_tree_block_csum_silent(buf, csum_size, csum_type);
return csum_tree_block_size(buf, csum_size, verify, csum_type);
}
struct extent_buffer *btrfs_find_tree_block(struct btrfs_fs_info *fs_info,
u64 bytenr, u32 blocksize)
{
return find_extent_buffer(&fs_info->extent_cache,
bytenr, blocksize);
}
struct extent_buffer* btrfs_find_create_tree_block(
struct btrfs_fs_info *fs_info, u64 bytenr)
{
return alloc_extent_buffer(fs_info, bytenr, fs_info->nodesize);
}
void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
u64 parent_transid)
{
struct extent_buffer *eb;
u64 length;
struct btrfs_multi_bio *multi = NULL;
struct btrfs_device *device;
eb = btrfs_find_tree_block(fs_info, bytenr, fs_info->nodesize);
if (!(eb && btrfs_buffer_uptodate(eb, parent_transid)) &&
!btrfs_map_block(fs_info, READ, bytenr, &length, &multi, 0,
NULL)) {
device = multi->stripes[0].dev;
device->total_ios++;
readahead(device->fd, multi->stripes[0].physical,
fs_info->nodesize);
}
free_extent_buffer(eb);
kfree(multi);
}
static int verify_parent_transid(struct extent_io_tree *io_tree,
struct extent_buffer *eb, u64 parent_transid,
int ignore)
{
int ret;
if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
return 0;
if (extent_buffer_uptodate(eb) &&
btrfs_header_generation(eb) == parent_transid) {
ret = 0;
goto out;
}
printk("parent transid verify failed on %llu wanted %llu found %llu\n",
(unsigned long long)eb->start,
(unsigned long long)parent_transid,
(unsigned long long)btrfs_header_generation(eb));
if (ignore) {
eb->flags |= EXTENT_BAD_TRANSID;
printk("Ignoring transid failure\n");
return 0;
}
ret = 1;
out:
clear_extent_buffer_uptodate(eb);
return ret;
}
int read_whole_eb(struct btrfs_fs_info *info, struct extent_buffer *eb, int mirror)
{
unsigned long offset = 0;
struct btrfs_multi_bio *multi = NULL;
struct btrfs_device *device;
int ret = 0;
u64 read_len;
unsigned long bytes_left = eb->len;
while (bytes_left) {
read_len = bytes_left;
device = NULL;
if (!info->on_restoring &&
eb->start != BTRFS_SUPER_INFO_OFFSET) {
ret = btrfs_map_block(info, READ, eb->start + offset,
&read_len, &multi, mirror, NULL);
if (ret) {
printk("Couldn't map the block %Lu\n", eb->start + offset);
kfree(multi);
return -EIO;
}
device = multi->stripes[0].dev;
if (device->fd <= 0) {
kfree(multi);
return -EIO;
}
eb->fd = device->fd;
device->total_ios++;
eb->dev_bytenr = multi->stripes[0].physical;
kfree(multi);
multi = NULL;
} else {
/* special case for restore metadump */
list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
if (device->devid == 1)
break;
}
eb->fd = device->fd;
eb->dev_bytenr = eb->start;
device->total_ios++;
}
if (read_len > bytes_left)
read_len = bytes_left;
ret = read_extent_from_disk(eb, offset, read_len);
if (ret)
return -EIO;
offset += read_len;
bytes_left -= read_len;
}
return 0;
}
struct extent_buffer* read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
u64 parent_transid)
{
int ret;
struct extent_buffer *eb;
u64 best_transid = 0;
u32 sectorsize = fs_info->sectorsize;
int mirror_num = 1;
int good_mirror = 0;
int candidate_mirror = 0;
int num_copies;
int ignore = 0;
/*
* Don't even try to create tree block for unaligned tree block
* bytenr.
* Such unaligned tree block will free overlapping extent buffer,
* causing use-after-free bugs for fuzzed images.
*/
if (bytenr < sectorsize || !IS_ALIGNED(bytenr, sectorsize)) {
error("tree block bytenr %llu is not aligned to sectorsize %u",
bytenr, sectorsize);
return ERR_PTR(-EIO);
}
eb = btrfs_find_create_tree_block(fs_info, bytenr);
if (!eb)
return ERR_PTR(-ENOMEM);
if (btrfs_buffer_uptodate(eb, parent_transid))
return eb;
num_copies = btrfs_num_copies(fs_info, eb->start, eb->len);
while (1) {
ret = read_whole_eb(fs_info, eb, mirror_num);
if (ret == 0 && csum_tree_block(fs_info, eb, 1) == 0 &&
check_tree_block(fs_info, eb) == 0 &&
verify_parent_transid(&fs_info->extent_cache, eb,
parent_transid, ignore) == 0) {
if (eb->flags & EXTENT_BAD_TRANSID &&
list_empty(&eb->recow)) {
list_add_tail(&eb->recow,
&fs_info->recow_ebs);
eb->refs++;
}
/*
* check_tree_block() is less strict to allow btrfs
* check to get raw eb with bad key order and fix it.
* But we still need to try to get a good copy if
* possible, or bad key order can go into tools like
* btrfs ins dump-tree.
*/
if (btrfs_header_level(eb))
ret = btrfs_check_node(fs_info, NULL, eb);
else
ret = btrfs_check_leaf(fs_info, NULL, eb);
if (!ret || candidate_mirror == mirror_num) {
btrfs_set_buffer_uptodate(eb);
return eb;
}
if (candidate_mirror <= 0)
candidate_mirror = mirror_num;
}
if (ignore) {
if (candidate_mirror > 0) {
mirror_num = candidate_mirror;
continue;
}
if (check_tree_block(fs_info, eb)) {
if (!fs_info->suppress_check_block_errors)
print_tree_block_error(fs_info, eb,
check_tree_block(fs_info, eb));
} else {
if (!fs_info->suppress_check_block_errors)
fprintf(stderr, "Csum didn't match\n");
}
ret = -EIO;
break;
}
if (num_copies == 1) {
ignore = 1;
continue;
}
if (btrfs_header_generation(eb) > best_transid) {
best_transid = btrfs_header_generation(eb);
good_mirror = mirror_num;
}
mirror_num++;
if (mirror_num > num_copies) {
if (candidate_mirror > 0)
mirror_num = candidate_mirror;
else
mirror_num = good_mirror;
ignore = 1;
continue;
}
}
/*
* We failed to read this tree block, it be should deleted right now
* to avoid stale cache populate the cache.
*/
free_extent_buffer_nocache(eb);
return ERR_PTR(ret);
}
int read_extent_data(struct btrfs_fs_info *fs_info, char *data, u64 logical,
u64 *len, int mirror)
{
u64 offset = 0;
struct btrfs_multi_bio *multi = NULL;
struct btrfs_device *device;
int ret = 0;
u64 max_len = *len;
ret = btrfs_map_block(fs_info, READ, logical, len, &multi, mirror,
NULL);
if (ret) {
fprintf(stderr, "Couldn't map the block %llu\n",
logical + offset);
goto err;
}
device = multi->stripes[0].dev;
if (*len > max_len)
*len = max_len;
if (device->fd < 0) {
ret = -EIO;
goto err;
}
ret = pread64(device->fd, data, *len, multi->stripes[0].physical);
if (ret != *len)
ret = -EIO;
else
ret = 0;
err:
kfree(multi);
return ret;
}
int write_and_map_eb(struct btrfs_fs_info *fs_info, struct extent_buffer *eb)
{
int ret;
int dev_nr;
u64 length;
u64 *raid_map = NULL;
struct btrfs_multi_bio *multi = NULL;
dev_nr = 0;
length = eb->len;
ret = btrfs_map_block(fs_info, WRITE, eb->start, &length,
&multi, 0, &raid_map);
if (ret < 0) {
errno = -ret;
error("failed to map bytenr %llu length %u: %m",
eb->start, eb->len);
goto out;
}
if (raid_map) {
ret = write_raid56_with_parity(fs_info, eb, multi,
length, raid_map);
if (ret < 0) {
errno = -ret;
error(
"failed to write raid56 stripe for bytenr %llu length %llu: %m",
eb->start, length);
goto out;
}
} else while (dev_nr < multi->num_stripes) {
eb->fd = multi->stripes[dev_nr].dev->fd;
eb->dev_bytenr = multi->stripes[dev_nr].physical;
multi->stripes[dev_nr].dev->total_ios++;
dev_nr++;
ret = write_extent_to_disk(eb);
if (ret < 0) {
errno = -ret;
error(
"failed to write bytenr %llu length %u devid %llu dev_bytenr %llu: %m",
eb->start, eb->len,
multi->stripes[dev_nr].dev->devid,
eb->dev_bytenr);
goto out;
}
}
out:
kfree(raid_map);
kfree(multi);
return 0;
}
int write_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
struct extent_buffer *eb)
{
if (check_tree_block(fs_info, eb)) {
print_tree_block_error(fs_info, eb,
check_tree_block(fs_info, eb));
BUG();
}
if (trans && !btrfs_buffer_uptodate(eb, trans->transid))
BUG();
btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
csum_tree_block(fs_info, eb, 0);
return write_and_map_eb(fs_info, eb);
}
void btrfs_setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
u64 objectid)
{
root->node = NULL;
root->commit_root = NULL;
root->ref_cows = 0;
root->track_dirty = 0;
root->fs_info = fs_info;
root->objectid = objectid;
root->last_trans = 0;
root->last_inode_alloc = 0;
INIT_LIST_HEAD(&root->dirty_list);
INIT_LIST_HEAD(&root->unaligned_extent_recs);
memset(&root->root_key, 0, sizeof(root->root_key));
memset(&root->root_item, 0, sizeof(root->root_item));
root->root_key.objectid = objectid;
}
static int find_and_setup_root(struct btrfs_root *tree_root,
struct btrfs_fs_info *fs_info,
u64 objectid, struct btrfs_root *root)
{
int ret;
u64 generation;
btrfs_setup_root(root, fs_info, objectid);
ret = btrfs_find_last_root(tree_root, objectid,
&root->root_item, &root->root_key);
if (ret)
return ret;
generation = btrfs_root_generation(&root->root_item);
root->node = read_tree_block(fs_info,
btrfs_root_bytenr(&root->root_item), generation);
if (!extent_buffer_uptodate(root->node))
return -EIO;
return 0;
}
static int find_and_setup_log_root(struct btrfs_root *tree_root,
struct btrfs_fs_info *fs_info,
struct btrfs_super_block *disk_super)
{
u64 blocknr = btrfs_super_log_root(disk_super);
struct btrfs_root *log_root = malloc(sizeof(struct btrfs_root));
if (!log_root)
return -ENOMEM;
if (blocknr == 0) {
free(log_root);
return 0;
}
btrfs_setup_root(log_root, fs_info,
BTRFS_TREE_LOG_OBJECTID);
log_root->node = read_tree_block(fs_info, blocknr,
btrfs_super_generation(disk_super) + 1);
fs_info->log_root_tree = log_root;
if (!extent_buffer_uptodate(log_root->node)) {
free_extent_buffer(log_root->node);
free(log_root);
fs_info->log_root_tree = NULL;
return -EIO;
}
return 0;
}
int btrfs_free_fs_root(struct btrfs_root *root)
{
if (root->node)
free_extent_buffer(root->node);
if (root->commit_root)
free_extent_buffer(root->commit_root);
kfree(root);
return 0;
}
static void __free_fs_root(struct rb_node *node)
{
struct btrfs_root *root;
root = container_of(node, struct btrfs_root, rb_node);
btrfs_free_fs_root(root);
}
FREE_RB_BASED_TREE(fs_roots, __free_fs_root);
struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
struct btrfs_key *location)
{
struct btrfs_root *root;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_path *path;
struct extent_buffer *l;
u64 generation;
int ret = 0;
root = calloc(1, sizeof(*root));
if (!root)
return ERR_PTR(-ENOMEM);
if (location->offset == (u64)-1) {
ret = find_and_setup_root(tree_root, fs_info,
location->objectid, root);
if (ret) {
free(root);
return ERR_PTR(ret);
}
goto insert;
}
btrfs_setup_root(root, fs_info,
location->objectid);
path = btrfs_alloc_path();
if (!path) {
free(root);
return ERR_PTR(-ENOMEM);
}
ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
if (ret != 0) {
if (ret > 0)
ret = -ENOENT;
goto out;
}
l = path->nodes[0];
read_extent_buffer(l, &root->root_item,
btrfs_item_ptr_offset(l, path->slots[0]),
sizeof(root->root_item));
memcpy(&root->root_key, location, sizeof(*location));
ret = 0;
out:
btrfs_free_path(path);
if (ret) {
free(root);
return ERR_PTR(ret);
}
generation = btrfs_root_generation(&root->root_item);
root->node = read_tree_block(fs_info,
btrfs_root_bytenr(&root->root_item), generation);
if (!extent_buffer_uptodate(root->node)) {
free(root);
return ERR_PTR(-EIO);
}
insert:
root->ref_cows = 1;
return root;
}
static int btrfs_fs_roots_compare_objectids(struct rb_node *node,
void *data)
{
u64 objectid = *((u64 *)data);
struct btrfs_root *root;
root = rb_entry(node, struct btrfs_root, rb_node);
if (objectid > root->objectid)
return 1;
else if (objectid < root->objectid)
return -1;
else
return 0;
}
int btrfs_fs_roots_compare_roots(struct rb_node *node1, struct rb_node *node2)
{
struct btrfs_root *root;
root = rb_entry(node2, struct btrfs_root, rb_node);
return btrfs_fs_roots_compare_objectids(node1, (void *)&root->objectid);
}
struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
struct btrfs_key *location)
{
struct btrfs_root *root;
struct rb_node *node;
int ret;
u64 objectid = location->objectid;
if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
return fs_info->tree_root;
if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
return fs_info->extent_root;
if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
return fs_info->chunk_root;
if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
return fs_info->dev_root;
if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
return fs_info->csum_root;
if (location->objectid == BTRFS_UUID_TREE_OBJECTID)
return fs_info->uuid_root ? fs_info->uuid_root : ERR_PTR(-ENOENT);
if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
return fs_info->quota_enabled ? fs_info->quota_root :
ERR_PTR(-ENOENT);
if (location->objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
return fs_info->free_space_root ? fs_info->free_space_root :
ERR_PTR(-ENOENT);
BUG_ON(location->objectid == BTRFS_TREE_RELOC_OBJECTID);
node = rb_search(&fs_info->fs_root_tree, (void *)&objectid,
btrfs_fs_roots_compare_objectids, NULL);
if (node)
return container_of(node, struct btrfs_root, rb_node);
root = btrfs_read_fs_root_no_cache(fs_info, location);
if (IS_ERR(root))
return root;
ret = rb_insert(&fs_info->fs_root_tree, &root->rb_node,
btrfs_fs_roots_compare_roots);
BUG_ON(ret);
return root;
}
void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
{
if (fs_info->quota_root)
free(fs_info->quota_root);
free(fs_info->tree_root);
free(fs_info->extent_root);
free(fs_info->chunk_root);
free(fs_info->dev_root);
free(fs_info->csum_root);
free(fs_info->free_space_root);
free(fs_info->uuid_root);
free(fs_info->super_copy);
free(fs_info->log_root_tree);
free(fs_info);
}
struct btrfs_fs_info *btrfs_new_fs_info(int writable, u64 sb_bytenr)
{
struct btrfs_fs_info *fs_info;
fs_info = calloc(1, sizeof(struct btrfs_fs_info));
if (!fs_info)
return NULL;
fs_info->tree_root = calloc(1, sizeof(struct btrfs_root));
fs_info->extent_root = calloc(1, sizeof(struct btrfs_root));
fs_info->chunk_root = calloc(1, sizeof(struct btrfs_root));
fs_info->dev_root = calloc(1, sizeof(struct btrfs_root));
fs_info->csum_root = calloc(1, sizeof(struct btrfs_root));
fs_info->quota_root = calloc(1, sizeof(struct btrfs_root));
fs_info->free_space_root = calloc(1, sizeof(struct btrfs_root));
fs_info->uuid_root = calloc(1, sizeof(struct btrfs_root));
fs_info->super_copy = calloc(1, BTRFS_SUPER_INFO_SIZE);
if (!fs_info->tree_root || !fs_info->extent_root ||
!fs_info->chunk_root || !fs_info->dev_root ||
!fs_info->csum_root || !fs_info->quota_root ||
!fs_info->free_space_root || !fs_info->uuid_root ||
!fs_info->super_copy)
goto free_all;
extent_io_tree_init(&fs_info->extent_cache);
extent_io_tree_init(&fs_info->free_space_cache);
extent_io_tree_init(&fs_info->pinned_extents);
extent_io_tree_init(&fs_info->extent_ins);
fs_info->block_group_cache_tree = RB_ROOT;
fs_info->excluded_extents = NULL;
fs_info->fs_root_tree = RB_ROOT;
cache_tree_init(&fs_info->mapping_tree.cache_tree);
INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
INIT_LIST_HEAD(&fs_info->space_info);
INIT_LIST_HEAD(&fs_info->recow_ebs);
if (!writable)
fs_info->readonly = 1;
fs_info->super_bytenr = sb_bytenr;
fs_info->data_alloc_profile = (u64)-1;
fs_info->metadata_alloc_profile = (u64)-1;
fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
return fs_info;
free_all:
btrfs_free_fs_info(fs_info);
return NULL;
}
int btrfs_check_fs_compatibility(struct btrfs_super_block *sb,
unsigned int flags)
{
u64 features;
features = btrfs_super_incompat_flags(sb) &
~BTRFS_FEATURE_INCOMPAT_SUPP;
if (features) {
printk("couldn't open because of unsupported "
"option features (%llx).\n",
(unsigned long long)features);
return -ENOTSUP;
}
features = btrfs_super_incompat_flags(sb);
if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
btrfs_set_super_incompat_flags(sb, features);
}
features = btrfs_super_compat_ro_flags(sb);
if (flags & OPEN_CTREE_WRITES) {
if (flags & OPEN_CTREE_INVALIDATE_FST) {
/* Clear the FREE_SPACE_TREE_VALID bit on disk... */
features &= ~BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID;
btrfs_set_super_compat_ro_flags(sb, features);
/* ... and ignore the free space tree bit. */
features &= ~BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE;
}
if (features & ~BTRFS_FEATURE_COMPAT_RO_SUPP) {
printk("couldn't open RDWR because of unsupported "
"option features (0x%llx)\n",
(unsigned long long)features);
return -ENOTSUP;
}
}
return 0;
}
static int find_best_backup_root(struct btrfs_super_block *super)
{
struct btrfs_root_backup *backup;
u64 orig_gen = btrfs_super_generation(super);
u64 gen = 0;
int best_index = 0;
int i;
for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
backup = super->super_roots + i;
if (btrfs_backup_tree_root_gen(backup) != orig_gen &&
btrfs_backup_tree_root_gen(backup) > gen) {
best_index = i;
gen = btrfs_backup_tree_root_gen(backup);
}
}
return best_index;
}
static int setup_root_or_create_block(struct btrfs_fs_info *fs_info,
unsigned flags,
struct btrfs_root *info_root,
u64 objectid, char *str)
{
struct btrfs_root *root = fs_info->tree_root;
int ret;
ret = find_and_setup_root(root, fs_info, objectid, info_root);
if (ret) {
if (!(flags & OPEN_CTREE_PARTIAL)) {
error("could not setup %s tree", str);
return -EIO;
}
warning("could not setup %s tree, skipping it", str);
/*
* Need a blank node here just so we don't screw up in the
* million of places that assume a root has a valid ->node
*/
info_root->node =
btrfs_find_create_tree_block(fs_info, 0);
if (!info_root->node)
return -ENOMEM;
clear_extent_buffer_uptodate(info_root->node);
}
return 0;
}
int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info, u64 root_tree_bytenr,
unsigned flags)
{
struct btrfs_super_block *sb = fs_info->super_copy;
struct btrfs_root *root;
struct btrfs_key key;
u64 generation;
int ret;
root = fs_info->tree_root;
btrfs_setup_root(root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
generation = btrfs_super_generation(sb);
if (!root_tree_bytenr && !(flags & OPEN_CTREE_BACKUP_ROOT)) {
root_tree_bytenr = btrfs_super_root(sb);
} else if (flags & OPEN_CTREE_BACKUP_ROOT) {
struct btrfs_root_backup *backup;
int index = find_best_backup_root(sb);
if (index >= BTRFS_NUM_BACKUP_ROOTS) {
fprintf(stderr, "Invalid backup root number\n");
return -EIO;
}
backup = fs_info->super_copy->super_roots + index;
root_tree_bytenr = btrfs_backup_tree_root(backup);
generation = btrfs_backup_tree_root_gen(backup);
}
root->node = read_tree_block(fs_info, root_tree_bytenr, generation);
if (!extent_buffer_uptodate(root->node)) {
fprintf(stderr, "Couldn't read tree root\n");
return -EIO;
}
ret = setup_root_or_create_block(fs_info, flags, fs_info->extent_root,
BTRFS_EXTENT_TREE_OBJECTID, "extent");
if (ret)
return ret;
fs_info->extent_root->track_dirty = 1;
ret = find_and_setup_root(root, fs_info, BTRFS_DEV_TREE_OBJECTID,
fs_info->dev_root);
if (ret) {
printk("Couldn't setup device tree\n");
return -EIO;
}
fs_info->dev_root->track_dirty = 1;
ret = setup_root_or_create_block(fs_info, flags, fs_info->csum_root,
BTRFS_CSUM_TREE_OBJECTID, "csum");
if (ret)
return ret;
fs_info->csum_root->track_dirty = 1;
ret = find_and_setup_root(root, fs_info, BTRFS_UUID_TREE_OBJECTID,
fs_info->uuid_root);
if (ret) {
free(fs_info->uuid_root);
fs_info->uuid_root = NULL;
} else {
fs_info->uuid_root->track_dirty = 1;
}
ret = find_and_setup_root(root, fs_info, BTRFS_QUOTA_TREE_OBJECTID,
fs_info->quota_root);
if (ret) {
free(fs_info->quota_root);
fs_info->quota_root = NULL;
} else {
fs_info->quota_enabled = 1;
}
if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
ret = find_and_setup_root(root, fs_info, BTRFS_FREE_SPACE_TREE_OBJECTID,
fs_info->free_space_root);
if (ret) {
free(fs_info->free_space_root);
fs_info->free_space_root = NULL;
printk("Couldn't read free space tree\n");
return -EIO;
}
fs_info->free_space_root->track_dirty = 1;
} else {
free(fs_info->free_space_root);
fs_info->free_space_root = NULL;
}
ret = find_and_setup_log_root(root, fs_info, sb);
if (ret) {
printk("Couldn't setup log root tree\n");
if (!(flags & OPEN_CTREE_PARTIAL))
return -EIO;
}
fs_info->generation = generation;
fs_info->last_trans_committed = generation;
if (extent_buffer_uptodate(fs_info->extent_root->node) &&
!(flags & OPEN_CTREE_NO_BLOCK_GROUPS)) {
ret = btrfs_read_block_groups(fs_info);
/*
* If we don't find any blockgroups (ENOENT) we're either
* restoring or creating the filesystem, where it's expected,
* anything else is error
*/
if (ret < 0 && ret != -ENOENT) {
errno = -ret;
error("failed to read block groups: %m");
return ret;
}
}
key.objectid = BTRFS_FS_TREE_OBJECTID;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = (u64)-1;
fs_info->fs_root = btrfs_read_fs_root(fs_info, &key);
if (IS_ERR(fs_info->fs_root))
return -EIO;
return 0;
}
void btrfs_release_all_roots(struct btrfs_fs_info *fs_info)
{
if (fs_info->free_space_root)
free_extent_buffer(fs_info->free_space_root->node);
if (fs_info->quota_root)
free_extent_buffer(fs_info->quota_root->node);
if (fs_info->csum_root)
free_extent_buffer(fs_info->csum_root->node);
if (fs_info->dev_root)
free_extent_buffer(fs_info->dev_root->node);
if (fs_info->extent_root)
free_extent_buffer(fs_info->extent_root->node);
if (fs_info->tree_root)
free_extent_buffer(fs_info->tree_root->node);
if (fs_info->log_root_tree)
free_extent_buffer(fs_info->log_root_tree->node);
if (fs_info->chunk_root)
free_extent_buffer(fs_info->chunk_root->node);
if (fs_info->uuid_root)
free_extent_buffer(fs_info->uuid_root->node);
}
static void free_map_lookup(struct cache_extent *ce)
{
struct map_lookup *map;
map = container_of(ce, struct map_lookup, ce);
kfree(map);
}
FREE_EXTENT_CACHE_BASED_TREE(mapping_cache, free_map_lookup);
void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info)
{
while (!list_empty(&fs_info->recow_ebs)) {
struct extent_buffer *eb;
eb = list_first_entry(&fs_info->recow_ebs,
struct extent_buffer, recow);
list_del_init(&eb->recow);
free_extent_buffer(eb);
}
free_mapping_cache_tree(&fs_info->mapping_tree.cache_tree);
extent_io_tree_cleanup(&fs_info->extent_cache);
extent_io_tree_cleanup(&fs_info->free_space_cache);
extent_io_tree_cleanup(&fs_info->pinned_extents);
extent_io_tree_cleanup(&fs_info->extent_ins);
}
int btrfs_scan_fs_devices(int fd, const char *path,
struct btrfs_fs_devices **fs_devices,
u64 sb_bytenr, unsigned sbflags,
int skip_devices)
{
u64 total_devs;
u64 dev_size;
off_t seek_ret;
int ret;
if (!sb_bytenr)
sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
seek_ret = lseek(fd, 0, SEEK_END);
if (seek_ret < 0)
return -errno;
dev_size = seek_ret;
lseek(fd, 0, SEEK_SET);
if (sb_bytenr > dev_size) {
error("superblock bytenr %llu is larger than device size %llu",
(unsigned long long)sb_bytenr,
(unsigned long long)dev_size);
return -EINVAL;
}
ret = btrfs_scan_one_device(fd, path, fs_devices,
&total_devs, sb_bytenr, sbflags);
if (ret) {
fprintf(stderr, "No valid Btrfs found on %s\n", path);
return ret;
}
if (!skip_devices && total_devs != 1) {
ret = btrfs_scan_devices(0);
if (ret)
return ret;
}
return 0;
}
int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info,
u64 chunk_root_bytenr)
{
struct btrfs_super_block *sb = fs_info->super_copy;
u64 generation;
int ret;
btrfs_setup_root(fs_info->chunk_root, fs_info,
BTRFS_CHUNK_TREE_OBJECTID);
ret = btrfs_read_sys_array(fs_info);
if (ret)
return ret;
generation = btrfs_super_chunk_root_generation(sb);
if (chunk_root_bytenr && !IS_ALIGNED(chunk_root_bytenr,
fs_info->sectorsize)) {
warning("chunk_root_bytenr %llu is unaligned to %u, ignore it",
chunk_root_bytenr, fs_info->sectorsize);
chunk_root_bytenr = 0;
}
if (!chunk_root_bytenr)
chunk_root_bytenr = btrfs_super_chunk_root(sb);
else
generation = 0;
fs_info->chunk_root->node = read_tree_block(fs_info,
chunk_root_bytenr,
generation);
if (!extent_buffer_uptodate(fs_info->chunk_root->node)) {
if (fs_info->ignore_chunk_tree_error) {
warning("cannot read chunk root, continue anyway");
fs_info->chunk_root = NULL;
return 0;
} else {
error("cannot read chunk root");
return -EIO;
}
}
if (!(btrfs_super_flags(sb) & BTRFS_SUPER_FLAG_METADUMP)) {
ret = btrfs_read_chunk_tree(fs_info);
if (ret) {
fprintf(stderr, "Couldn't read chunk tree\n");
return ret;
}
}
return 0;
}
static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
u64 sb_bytenr,
u64 root_tree_bytenr,
u64 chunk_root_bytenr,
unsigned flags)
{
struct btrfs_fs_info *fs_info;
struct btrfs_super_block *disk_super;
struct btrfs_fs_devices *fs_devices = NULL;
struct extent_buffer *eb;
int ret;
int oflags;
unsigned sbflags = SBREAD_DEFAULT;
if (sb_bytenr == 0)
sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
/* try to drop all the caches */
if (posix_fadvise(fp, 0, 0, POSIX_FADV_DONTNEED))
fprintf(stderr, "Warning, could not drop caches\n");
fs_info = btrfs_new_fs_info(flags & OPEN_CTREE_WRITES, sb_bytenr);
if (!fs_info) {
fprintf(stderr, "Failed to allocate memory for fs_info\n");
return NULL;
}
if (flags & OPEN_CTREE_RESTORE)
fs_info->on_restoring = 1;
if (flags & OPEN_CTREE_SUPPRESS_CHECK_BLOCK_ERRORS)
fs_info->suppress_check_block_errors = 1;
if (flags & OPEN_CTREE_IGNORE_FSID_MISMATCH)
fs_info->ignore_fsid_mismatch = 1;
if (flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR)
fs_info->ignore_chunk_tree_error = 1;
if (flags & OPEN_CTREE_HIDE_NAMES)
fs_info->hide_names = 1;
if ((flags & OPEN_CTREE_RECOVER_SUPER)
&& (flags & OPEN_CTREE_TEMPORARY_SUPER)) {
fprintf(stderr,
"cannot open a filesystem with temporary super block for recovery");
goto out;
}
if (flags & OPEN_CTREE_TEMPORARY_SUPER)
sbflags = SBREAD_TEMPORARY;
if (flags & OPEN_CTREE_IGNORE_FSID_MISMATCH)
sbflags |= SBREAD_IGNORE_FSID_MISMATCH;
ret = btrfs_scan_fs_devices(fp, path, &fs_devices, sb_bytenr, sbflags,
(flags & OPEN_CTREE_NO_DEVICES));
if (ret)
goto out;
fs_info->fs_devices = fs_devices;
if (flags & OPEN_CTREE_WRITES)
oflags = O_RDWR;
else
oflags = O_RDONLY;
if (flags & OPEN_CTREE_EXCLUSIVE)
oflags |= O_EXCL;
ret = btrfs_open_devices(fs_devices, oflags);
if (ret)
goto out;
disk_super = fs_info->super_copy;
if (flags & OPEN_CTREE_RECOVER_SUPER)
ret = btrfs_read_dev_super(fs_devices->latest_bdev, disk_super,
sb_bytenr, SBREAD_RECOVER);
else
ret = btrfs_read_dev_super(fp, disk_super, sb_bytenr,
sbflags);
if (ret) {
printk("No valid btrfs found\n");
goto out_devices;
}
if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID &&
!fs_info->ignore_fsid_mismatch) {
fprintf(stderr, "ERROR: Filesystem UUID change in progress\n");
goto out_devices;
}
ASSERT(!memcmp(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE));
if (btrfs_fs_incompat(fs_info, METADATA_UUID))
ASSERT(!memcmp(disk_super->metadata_uuid,
fs_devices->metadata_uuid, BTRFS_FSID_SIZE));
fs_info->sectorsize = btrfs_super_sectorsize(disk_super);
fs_info->nodesize = btrfs_super_nodesize(disk_super);
fs_info->stripesize = btrfs_super_stripesize(disk_super);
ret = btrfs_check_fs_compatibility(fs_info->super_copy, flags);
if (ret)
goto out_devices;
ret = btrfs_setup_chunk_tree_and_device_map(fs_info, chunk_root_bytenr);
if (ret)
goto out_chunk;
/* Chunk tree root is unable to read, return directly */
if (!fs_info->chunk_root)
return fs_info;
eb = fs_info->chunk_root->node;
read_extent_buffer(eb, fs_info->chunk_tree_uuid,
btrfs_header_chunk_tree_uuid(eb),
BTRFS_UUID_SIZE);
ret = btrfs_setup_all_roots(fs_info, root_tree_bytenr, flags);
if (ret && !(flags & __OPEN_CTREE_RETURN_CHUNK_ROOT) &&
!fs_info->ignore_chunk_tree_error)
goto out_chunk;
return fs_info;
out_chunk:
btrfs_release_all_roots(fs_info);
btrfs_cleanup_all_caches(fs_info);
out_devices:
btrfs_close_devices(fs_devices);
out:
btrfs_free_fs_info(fs_info);
return NULL;
}
struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
u64 sb_bytenr, u64 root_tree_bytenr,
u64 chunk_root_bytenr,
unsigned flags)
{
int fp;
int ret;
struct btrfs_fs_info *info;
int oflags = O_RDWR;
struct stat st;
ret = stat(filename, &st);
if (ret < 0) {
error("cannot stat '%s': %m", filename);
return NULL;
}
if (!(((st.st_mode & S_IFMT) == S_IFREG) || ((st.st_mode & S_IFMT) == S_IFBLK))) {
error("not a regular file or block device: %s", filename);
return NULL;
}
if (!(flags & OPEN_CTREE_WRITES))
oflags = O_RDONLY;
fp = open(filename, oflags);
if (fp < 0) {
error("cannot open '%s': %m", filename);
return NULL;
}
info = __open_ctree_fd(fp, filename, sb_bytenr, root_tree_bytenr,
chunk_root_bytenr, flags);
close(fp);
return info;
}
struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr,
unsigned flags)
{
struct btrfs_fs_info *info;
/* This flags may not return fs_info with any valid root */
BUG_ON(flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR);
info = open_ctree_fs_info(filename, sb_bytenr, 0, 0, flags);
if (!info)
return NULL;
if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
return info->chunk_root;
return info->fs_root;
}
struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
unsigned flags)
{
struct btrfs_fs_info *info;
/* This flags may not return fs_info with any valid root */
if (flags & OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR) {
error("invalid open_ctree flags: 0x%llx",
(unsigned long long)flags);
return NULL;
}
info = __open_ctree_fd(fp, path, sb_bytenr, 0, 0, flags);
if (!info)
return NULL;
if (flags & __OPEN_CTREE_RETURN_CHUNK_ROOT)
return info->chunk_root;
return info->fs_root;
}
/*
* Check if the super is valid:
* - nodesize/sectorsize - minimum, maximum, alignment
* - tree block starts - alignment
* - number of devices - something sane
* - sys array size - maximum
*/
int btrfs_check_super(struct btrfs_super_block *sb, unsigned sbflags)
{
u8 result[BTRFS_CSUM_SIZE];
u16 csum_type;
int csum_size;
u8 *metadata_uuid;
if (btrfs_super_magic(sb) != BTRFS_MAGIC) {
if (btrfs_super_magic(sb) == BTRFS_MAGIC_TEMPORARY) {
if (!(sbflags & SBREAD_TEMPORARY)) {
error("superblock magic doesn't match");
return -EIO;
}
}
}
csum_type = btrfs_super_csum_type(sb);
if (csum_type >= btrfs_super_num_csums()) {
error("unsupported checksum algorithm %u", csum_type);
return -EIO;
}
csum_size = btrfs_super_csum_size(sb);
btrfs_csum_data(csum_type, (u8 *)sb + BTRFS_CSUM_SIZE,
result, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
if (memcmp(result, sb->csum, csum_size)) {
error("superblock checksum mismatch");
return -EIO;
}
if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) {
error("tree_root level too big: %d >= %d",
btrfs_super_root_level(sb), BTRFS_MAX_LEVEL);
goto error_out;
}
if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) {
error("chunk_root level too big: %d >= %d",
btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL);
goto error_out;
}
if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) {
error("log_root level too big: %d >= %d",
btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL);
goto error_out;
}
if (!IS_ALIGNED(btrfs_super_root(sb), 4096)) {
error("tree_root block unaligned: %llu", btrfs_super_root(sb));
goto error_out;
}
if (!IS_ALIGNED(btrfs_super_chunk_root(sb), 4096)) {
error("chunk_root block unaligned: %llu",
btrfs_super_chunk_root(sb));
goto error_out;
}
if (!IS_ALIGNED(btrfs_super_log_root(sb), 4096)) {
error("log_root block unaligned: %llu",
btrfs_super_log_root(sb));
goto error_out;
}
if (btrfs_super_nodesize(sb) < 4096) {
error("nodesize too small: %u < 4096",
btrfs_super_nodesize(sb));
goto error_out;
}
if (!IS_ALIGNED(btrfs_super_nodesize(sb), 4096)) {
error("nodesize unaligned: %u", btrfs_super_nodesize(sb));
goto error_out;
}
if (btrfs_super_sectorsize(sb) < 4096) {
error("sectorsize too small: %u < 4096",
btrfs_super_sectorsize(sb));
goto error_out;
}
if (!IS_ALIGNED(btrfs_super_sectorsize(sb), 4096)) {
error("sectorsize unaligned: %u", btrfs_super_sectorsize(sb));
goto error_out;
}
if (btrfs_super_total_bytes(sb) == 0) {
error("invalid total_bytes 0");
goto error_out;
}
if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) {
error("invalid bytes_used %llu", btrfs_super_bytes_used(sb));
goto error_out;
}
if ((btrfs_super_stripesize(sb) != 4096)
&& (btrfs_super_stripesize(sb) != btrfs_super_sectorsize(sb))) {
error("invalid stripesize %u", btrfs_super_stripesize(sb));
goto error_out;
}
if (btrfs_super_incompat_flags(sb) & BTRFS_FEATURE_INCOMPAT_METADATA_UUID)
metadata_uuid = sb->metadata_uuid;
else
metadata_uuid = sb->fsid;
if (memcmp(metadata_uuid, sb->dev_item.fsid, BTRFS_FSID_SIZE) != 0) {
char fsid[BTRFS_UUID_UNPARSED_SIZE];
char dev_fsid[BTRFS_UUID_UNPARSED_SIZE];
uuid_unparse(sb->metadata_uuid, fsid);
uuid_unparse(sb->dev_item.fsid, dev_fsid);
if (sbflags & SBREAD_IGNORE_FSID_MISMATCH) {
warning("ignored: dev_item fsid mismatch: %s != %s",
dev_fsid, fsid);
} else {
error("dev_item UUID does not match fsid: %s != %s",
dev_fsid, fsid);
goto error_out;
}
}
/*
* Hint to catch really bogus numbers, bitflips or so
*/
if (btrfs_super_num_devices(sb) > (1UL << 31)) {
warning("suspicious number of devices: %llu",
btrfs_super_num_devices(sb));
}
if (btrfs_super_num_devices(sb) == 0) {
error("number of devices is 0");
goto error_out;
}
/*
* Obvious sys_chunk_array corruptions, it must hold at least one key
* and one chunk
*/
if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
error("system chunk array too big %u > %u",
btrfs_super_sys_array_size(sb),
BTRFS_SYSTEM_CHUNK_ARRAY_SIZE);
goto error_out;
}
if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key)
+ sizeof(struct btrfs_chunk)) {
error("system chunk array too small %u < %zu",
btrfs_super_sys_array_size(sb),
sizeof(struct btrfs_disk_key) +
sizeof(struct btrfs_chunk));
goto error_out;
}
return 0;
error_out:
error("superblock checksum matches but it has invalid members");
return -EIO;
}
/*
* btrfs_read_dev_super - read a valid superblock from a block device
* @fd: file descriptor of the device
* @sb: buffer where the superblock is going to be read in
* @sb_bytenr: offset of the particular superblock copy we want
* @sbflags: flags controlling how the superblock is read
*
* This function is used by various btrfs commands to obtain a valid superblock.
*
* It's mode of operation is controlled by the @sb_bytenr and @sbdflags
* parameters. If SBREAD_RECOVER flag is set and @sb_bytenr is
* BTRFS_SUPER_INFO_OFFSET then the function reads all 3 superblock copies and
* returns the newest one. If SBREAD_RECOVER is not set then only a single
* copy is read, which one is decided by @sb_bytenr. If @sb_bytenr !=
* BTRFS_SUPER_INFO_OFFSET then the @sbflags is effectively ignored and only a
* single copy is read.
*/
int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr,
unsigned sbflags)
{
u8 fsid[BTRFS_FSID_SIZE];
u8 metadata_uuid[BTRFS_FSID_SIZE];
int fsid_is_initialized = 0;
char tmp[BTRFS_SUPER_INFO_SIZE];
struct btrfs_super_block *buf = (struct btrfs_super_block *)tmp;
int i;
int ret;
int max_super = sbflags & SBREAD_RECOVER ? BTRFS_SUPER_MIRROR_MAX : 1;
u64 transid = 0;
bool metadata_uuid_set = false;
u64 bytenr;
if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) {
ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
/* real error */
if (ret < 0)
return -errno;
/* Not large enough sb, return -ENOENT instead of normal -EIO */
if (ret < BTRFS_SUPER_INFO_SIZE)
return -ENOENT;
if (btrfs_super_bytenr(buf) != sb_bytenr)
return -EIO;
ret = btrfs_check_super(buf, sbflags);
if (ret < 0)
return ret;
memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE);
return 0;
}
/*
* we would like to check all the supers, but that would make
* a btrfs mount succeed after a mkfs from a different FS.
* So, we need to add a special mount option to scan for
* later supers, using BTRFS_SUPER_MIRROR_MAX instead
*/
for (i = 0; i < max_super; i++) {
bytenr = btrfs_sb_offset(i);
ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, bytenr);
if (ret < BTRFS_SUPER_INFO_SIZE)
break;
if (btrfs_super_bytenr(buf) != bytenr )
continue;
/* if magic is NULL, the device was removed */
if (btrfs_super_magic(buf) == 0 && i == 0)
break;
if (btrfs_check_super(buf, sbflags))
continue;
if (!fsid_is_initialized) {
if (btrfs_super_incompat_flags(buf) &
BTRFS_FEATURE_INCOMPAT_METADATA_UUID) {
metadata_uuid_set = true;
memcpy(metadata_uuid, buf->metadata_uuid,
sizeof(metadata_uuid));
}
memcpy(fsid, buf->fsid, sizeof(fsid));
fsid_is_initialized = 1;
} else if (memcmp(fsid, buf->fsid, sizeof(fsid)) ||
(metadata_uuid_set && memcmp(metadata_uuid,
buf->metadata_uuid,
sizeof(metadata_uuid)))) {
/*
* the superblocks (the original one and
* its backups) contain data of different
* filesystems -> the super cannot be trusted
*/
continue;
}
if (btrfs_super_generation(buf) > transid) {
memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE);
transid = btrfs_super_generation(buf);
}
}
return transid > 0 ? 0 : -1;
}
static int write_dev_supers(struct btrfs_fs_info *fs_info,
struct btrfs_super_block *sb,
struct btrfs_device *device)
{
u64 bytenr;
u8 result[BTRFS_CSUM_SIZE];
int i, ret;
u16 csum_type = btrfs_super_csum_type(sb);
/*
* We need to write super block after all metadata written.
* This is the equivalent of kernel pre-flush for FUA.
*/
ret = fsync(device->fd);
if (ret < 0) {
error(
"failed to write super block for devid %llu: flush error: %m",
device->devid);
return -errno;
}
if (fs_info->super_bytenr != BTRFS_SUPER_INFO_OFFSET) {
btrfs_set_super_bytenr(sb, fs_info->super_bytenr);
btrfs_csum_data(csum_type, (u8 *)sb + BTRFS_CSUM_SIZE, result,
BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
memcpy(&sb->csum[0], result, BTRFS_CSUM_SIZE);
/*
* super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
* zero filled, we can use it directly
*/
ret = pwrite64(device->fd, fs_info->super_copy,
BTRFS_SUPER_INFO_SIZE,
fs_info->super_bytenr);
if (ret != BTRFS_SUPER_INFO_SIZE) {
errno = EIO;
error(
"failed to write super block for devid %llu: write error: %m",
device->devid);
return -EIO;
}
ret = fsync(device->fd);
if (ret < 0) {
error(
"failed to write super block for devid %llu: flush error: %m",
device->devid);
return -errno;
}
return 0;
}
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
if (bytenr + BTRFS_SUPER_INFO_SIZE > device->total_bytes)
break;
btrfs_set_super_bytenr(sb, bytenr);
btrfs_csum_data(csum_type, (u8 *)sb + BTRFS_CSUM_SIZE, result,
BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
memcpy(&sb->csum[0], result, BTRFS_CSUM_SIZE);
/*
* super_copy is BTRFS_SUPER_INFO_SIZE bytes and is
* zero filled, we can use it directly
*/
ret = pwrite64(device->fd, fs_info->super_copy,
BTRFS_SUPER_INFO_SIZE, bytenr);
if (ret != BTRFS_SUPER_INFO_SIZE) {
errno = EIO;
error(
"failed to write super block for devid %llu: write error: %m",
device->devid);
return -errno;
}
/*
* Flush after the primary sb write, this is the equivalent of
* kernel post-flush for FUA write.
*/
if (i == 0) {
ret = fsync(device->fd);
if (ret < 0) {
error(
"failed to write super block for devid %llu: flush error: %m",
device->devid);
return -errno;
}
}
}
return 0;
}
/*
* copy all the root pointers into the super backup array.
* this will bump the backup pointer by one when it is
* done
*/
static void backup_super_roots(struct btrfs_fs_info *info)
{
struct btrfs_root_backup *root_backup;
int next_backup;
int last_backup;
last_backup = find_best_backup_root(info->super_copy);
next_backup = (last_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
/* just overwrite the last backup if we're at the same generation */
root_backup = info->super_copy->super_roots + last_backup;
if (btrfs_backup_tree_root_gen(root_backup) ==
btrfs_header_generation(info->tree_root->node))
next_backup = last_backup;
root_backup = info->super_copy->super_roots + next_backup;
/*
* make sure all of our padding and empty slots get zero filled
* regardless of which ones we use today
*/
memset(root_backup, 0, sizeof(*root_backup));
btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
btrfs_set_backup_tree_root_gen(root_backup,
btrfs_header_generation(info->tree_root->node));
btrfs_set_backup_tree_root_level(root_backup,
btrfs_header_level(info->tree_root->node));
btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
btrfs_set_backup_chunk_root_gen(root_backup,
btrfs_header_generation(info->chunk_root->node));
btrfs_set_backup_chunk_root_level(root_backup,
btrfs_header_level(info->chunk_root->node));
btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
btrfs_set_backup_extent_root_gen(root_backup,
btrfs_header_generation(info->extent_root->node));
btrfs_set_backup_extent_root_level(root_backup,
btrfs_header_level(info->extent_root->node));
/*
* we might commit during log recovery, which happens before we set
* the fs_root. Make sure it is valid before we fill it in.
*/
if (info->fs_root && info->fs_root->node) {
btrfs_set_backup_fs_root(root_backup,
info->fs_root->node->start);
btrfs_set_backup_fs_root_gen(root_backup,
btrfs_header_generation(info->fs_root->node));
btrfs_set_backup_fs_root_level(root_backup,
btrfs_header_level(info->fs_root->node));
}
btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
btrfs_set_backup_dev_root_gen(root_backup,
btrfs_header_generation(info->dev_root->node));
btrfs_set_backup_dev_root_level(root_backup,
btrfs_header_level(info->dev_root->node));
btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
btrfs_set_backup_csum_root_gen(root_backup,
btrfs_header_generation(info->csum_root->node));
btrfs_set_backup_csum_root_level(root_backup,
btrfs_header_level(info->csum_root->node));
btrfs_set_backup_total_bytes(root_backup,
btrfs_super_total_bytes(info->super_copy));
btrfs_set_backup_bytes_used(root_backup,
btrfs_super_bytes_used(info->super_copy));
btrfs_set_backup_num_devices(root_backup,
btrfs_super_num_devices(info->super_copy));
};
int write_all_supers(struct btrfs_fs_info *fs_info)
{
struct list_head *head = &fs_info->fs_devices->devices;
struct btrfs_device *dev;
struct btrfs_super_block *sb;
struct btrfs_dev_item *dev_item;
int ret;
u64 flags;
backup_super_roots(fs_info);
sb = fs_info->super_copy;
dev_item = &sb->dev_item;
list_for_each_entry(dev, head, dev_list) {
if (!dev->writeable)
continue;
btrfs_set_stack_device_generation(dev_item, 0);
btrfs_set_stack_device_type(dev_item, dev->type);
btrfs_set_stack_device_id(dev_item, dev->devid);
btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used);
btrfs_set_stack_device_io_align(dev_item, dev->io_align);
btrfs_set_stack_device_io_width(dev_item, dev->io_width);
btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
memcpy(dev_item->fsid, fs_info->fs_devices->metadata_uuid,
BTRFS_FSID_SIZE);
flags = btrfs_super_flags(sb);
btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
ret = write_dev_supers(fs_info, sb, dev);
if (ret < 0)
return ret;
}
return 0;
}
int write_ctree_super(struct btrfs_trans_handle *trans)
{
int ret;
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_root *chunk_root = fs_info->chunk_root;
if (fs_info->readonly)
return 0;
btrfs_set_super_generation(fs_info->super_copy,
trans->transid);
btrfs_set_super_root(fs_info->super_copy,
tree_root->node->start);
btrfs_set_super_root_level(fs_info->super_copy,
btrfs_header_level(tree_root->node));
btrfs_set_super_chunk_root(fs_info->super_copy,
chunk_root->node->start);
btrfs_set_super_chunk_root_level(fs_info->super_copy,
btrfs_header_level(chunk_root->node));
btrfs_set_super_chunk_root_generation(fs_info->super_copy,
btrfs_header_generation(chunk_root->node));
ret = write_all_supers(fs_info);
if (ret)
fprintf(stderr, "failed to write new super block err %d\n", ret);
return ret;
}
int close_ctree_fs_info(struct btrfs_fs_info *fs_info)
{
int ret;
int err = 0;
struct btrfs_trans_handle *trans;
struct btrfs_root *root = fs_info->tree_root;
if (fs_info->last_trans_committed !=
fs_info->generation) {
BUG_ON(!root);
trans = btrfs_start_transaction(root, 1);
if (IS_ERR(trans)) {
err = PTR_ERR(trans);
goto skip_commit;
}
btrfs_commit_transaction(trans, root);
trans = btrfs_start_transaction(root, 1);
BUG_ON(IS_ERR(trans));
ret = commit_tree_roots(trans, fs_info);
BUG_ON(ret);
ret = __commit_transaction(trans, root);
BUG_ON(ret);
ret = write_ctree_super(trans);
kfree(trans);
if (ret) {
err = ret;
goto skip_commit;
}
}
if (fs_info->finalize_on_close) {
btrfs_set_super_magic(fs_info->super_copy, BTRFS_MAGIC);
root->fs_info->finalize_on_close = 0;
ret = write_all_supers(fs_info);
if (ret)
fprintf(stderr,
"failed to write new super block err %d\n", ret);
}
skip_commit:
btrfs_free_block_groups(fs_info);
free_fs_roots_tree(&fs_info->fs_root_tree);
btrfs_release_all_roots(fs_info);
ret = btrfs_close_devices(fs_info->fs_devices);
btrfs_cleanup_all_caches(fs_info);
btrfs_free_fs_info(fs_info);
if (!err)
err = ret;
return err;
}
int clean_tree_block(struct extent_buffer *eb)
{
return clear_extent_buffer_dirty(eb);
}
void btrfs_mark_buffer_dirty(struct extent_buffer *eb)
{
set_extent_buffer_dirty(eb);
}
int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
{
int ret;
ret = extent_buffer_uptodate(buf);
if (!ret)
return ret;
ret = verify_parent_transid(&buf->fs_info->extent_cache, buf,
parent_transid, 1);
return !ret;
}
int btrfs_set_buffer_uptodate(struct extent_buffer *eb)
{
return set_extent_buffer_uptodate(eb);
}
struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
u64 objectid)
{
struct extent_buffer *leaf;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_root *root;
struct btrfs_key key;
int ret = 0;
root = kzalloc(sizeof(*root), GFP_KERNEL);
if (!root)
return ERR_PTR(-ENOMEM);
btrfs_setup_root(root, fs_info, objectid);
root->root_key.objectid = objectid;
root->root_key.type = BTRFS_ROOT_ITEM_KEY;
root->root_key.offset = 0;
leaf = btrfs_alloc_free_block(trans, root, fs_info->nodesize, objectid,
NULL, 0, 0, 0);
if (IS_ERR(leaf)) {
ret = PTR_ERR(leaf);
leaf = NULL;
goto fail;
}
memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
btrfs_set_header_bytenr(leaf, leaf->start);
btrfs_set_header_generation(leaf, trans->transid);
btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
btrfs_set_header_owner(leaf, objectid);
root->node = leaf;
write_extent_buffer(leaf, fs_info->fs_devices->metadata_uuid,
btrfs_header_fsid(), BTRFS_FSID_SIZE);
write_extent_buffer(leaf, fs_info->chunk_tree_uuid,
btrfs_header_chunk_tree_uuid(leaf),
BTRFS_UUID_SIZE);
btrfs_mark_buffer_dirty(leaf);
extent_buffer_get(root->node);
root->commit_root = root->node;
root->track_dirty = 1;
root->root_item.flags = 0;
root->root_item.byte_limit = 0;
btrfs_set_root_bytenr(&root->root_item, leaf->start);
btrfs_set_root_generation(&root->root_item, trans->transid);
btrfs_set_root_level(&root->root_item, 0);
btrfs_set_root_refs(&root->root_item, 1);
btrfs_set_root_used(&root->root_item, leaf->len);
btrfs_set_root_last_snapshot(&root->root_item, 0);
btrfs_set_root_dirid(&root->root_item, 0);
memset(root->root_item.uuid, 0, BTRFS_UUID_SIZE);
root->root_item.drop_level = 0;
key.objectid = objectid;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = 0;
ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item);
if (ret)
goto fail;
return root;
fail:
if (leaf)
free_extent_buffer(leaf);
kfree(root);
return ERR_PTR(ret);
}