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btrfs-progs/disk-io.c

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/*
* 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.
*/
#define _XOPEN_SOURCE 600
#define __USE_XOPEN2K
#define _GNU_SOURCE 1
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include "kerncompat.h"
#include "radix-tree.h"
#include "ctree.h"
#include "disk-io.h"
#include "volumes.h"
#include "transaction.h"
#include "crc32c.h"
#include "utils.h"
#include "print-tree.h"
static int close_all_devices(struct btrfs_fs_info *fs_info);
static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf)
{
struct btrfs_fs_devices *fs_devices;
int ret = 1;
if (buf->start != btrfs_header_bytenr(buf)) {
printk("Check tree block failed, want=%Lu, have=%Lu\n",
buf->start, btrfs_header_bytenr(buf));
return ret;
}
fs_devices = root->fs_info->fs_devices;
while (fs_devices) {
if (!memcmp_extent_buffer(buf, fs_devices->fsid,
(unsigned long)btrfs_header_fsid(buf),
BTRFS_FSID_SIZE)) {
ret = 0;
break;
}
fs_devices = fs_devices->seed;
}
return ret;
}
u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
{
return crc32c(seed, data, len);
}
void btrfs_csum_final(u32 crc, char *result)
{
*(__le32 *)result = ~cpu_to_le32(crc);
}
int csum_tree_block_size(struct extent_buffer *buf, u16 csum_size,
int verify)
{
char *result;
u32 len;
u32 crc = ~(u32)0;
result = malloc(csum_size * sizeof(char));
if (!result)
return 1;
len = buf->len - BTRFS_CSUM_SIZE;
crc = crc32c(crc, buf->data + BTRFS_CSUM_SIZE, len);
btrfs_csum_final(crc, result);
if (verify) {
if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
printk("checksum verify failed on %llu found %X "
"wanted %X\n", (unsigned long long)buf->start,
*((int *)result), *((char *)buf->data));
free(result);
return 1;
}
} else {
write_extent_buffer(buf, result, 0, csum_size);
}
free(result);
return 0;
}
int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
int verify)
{
u16 csum_size =
btrfs_super_csum_size(&root->fs_info->super_copy);
return csum_tree_block_size(buf, csum_size, verify);
}
struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
u64 bytenr, u32 blocksize)
{
return find_extent_buffer(&root->fs_info->extent_cache,
bytenr, blocksize);
}
struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
u64 bytenr, u32 blocksize)
{
return alloc_extent_buffer(&root->fs_info->extent_cache, bytenr,
blocksize);
}
int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
u64 parent_transid)
{
int ret;
struct extent_buffer *eb;
u64 length;
struct btrfs_multi_bio *multi = NULL;
struct btrfs_device *device;
eb = btrfs_find_tree_block(root, bytenr, blocksize);
if (eb && btrfs_buffer_uptodate(eb, parent_transid)) {
free_extent_buffer(eb);
return 0;
}
length = blocksize;
ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
bytenr, &length, &multi, 0, NULL);
BUG_ON(ret);
device = multi->stripes[0].dev;
device->total_ios++;
blocksize = min(blocksize, (u32)(64 * 1024));
readahead(device->fd, multi->stripes[0].physical, blocksize);
kfree(multi);
return 0;
}
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) {
printk("Ignoring transid failure\n");
return 0;
}
ret = 1;
out:
clear_extent_buffer_uptodate(io_tree, eb);
return ret;
}
static 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;
ret = btrfs_map_block(&info->mapping_tree, 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;
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_root *root, u64 bytenr,
u32 blocksize, u64 parent_transid)
{
int ret;
struct extent_buffer *eb;
u64 best_transid = 0;
int mirror_num = 0;
int good_mirror = 0;
int num_copies;
int ignore = 0;
eb = btrfs_find_create_tree_block(root, bytenr, blocksize);
if (!eb)
return NULL;
if (btrfs_buffer_uptodate(eb, parent_transid))
return eb;
while (1) {
ret = read_whole_eb(root->fs_info, eb, mirror_num);
if (ret == 0 && check_tree_block(root, eb) == 0 &&
csum_tree_block(root, eb, 1) == 0 &&
verify_parent_transid(eb->tree, eb, parent_transid, ignore)
== 0) {
btrfs_set_buffer_uptodate(eb);
return eb;
}
if (ignore) {
if (check_tree_block(root, eb))
printk("read block failed check_tree_block\n");
else
printk("Csum didn't match\n");
break;
}
num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
eb->start, eb->len);
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) {
mirror_num = good_mirror;
ignore = 1;
continue;
}
}
free_extent_buffer(eb);
return NULL;
}
static int rmw_eb(struct btrfs_fs_info *info,
struct extent_buffer *eb, struct extent_buffer *orig_eb)
{
int ret;
unsigned long orig_off = 0;
unsigned long dest_off = 0;
unsigned long copy_len = eb->len;
ret = read_whole_eb(info, eb, 0);
if (ret)
return ret;
if (eb->start + eb->len <= orig_eb->start ||
eb->start >= orig_eb->start + orig_eb->len)
return 0;
/*
* | ----- orig_eb ------- |
* | ----- stripe ------- |
* | ----- orig_eb ------- |
* | ----- orig_eb ------- |
*/
if (eb->start > orig_eb->start)
orig_off = eb->start - orig_eb->start;
if (orig_eb->start > eb->start)
dest_off = orig_eb->start - eb->start;
if (copy_len > orig_eb->len - orig_off)
copy_len = orig_eb->len - orig_off;
if (copy_len > eb->len - dest_off)
copy_len = eb->len - dest_off;
memcpy(eb->data + dest_off, orig_eb->data + orig_off, copy_len);
return 0;
}
static void split_eb_for_raid56(struct btrfs_fs_info *info,
struct extent_buffer *orig_eb,
struct extent_buffer **ebs,
u64 stripe_len, u64 *raid_map,
int num_stripes)
{
struct extent_buffer *eb;
u64 start = orig_eb->start;
u64 this_eb_start;
int i;
int ret;
for (i = 0; i < num_stripes; i++) {
if (raid_map[i] >= BTRFS_RAID5_P_STRIPE)
break;
eb = malloc(sizeof(struct extent_buffer) + stripe_len);
if (!eb)
BUG();
memset(eb, 0, sizeof(struct extent_buffer) + stripe_len);
eb->start = raid_map[i];
eb->len = stripe_len;
eb->refs = 1;
eb->flags = 0;
eb->fd = -1;
eb->dev_bytenr = (u64)-1;
this_eb_start = raid_map[i];
if (start > this_eb_start ||
start + orig_eb->len < this_eb_start + stripe_len) {
ret = rmw_eb(info, eb, orig_eb);
BUG_ON(ret);
} else {
memcpy(eb->data, orig_eb->data + eb->start - start, stripe_len);
}
ebs[i] = eb;
}
}
static int write_raid56_with_parity(struct btrfs_fs_info *info,
struct extent_buffer *eb,
struct btrfs_multi_bio *multi,
u64 stripe_len, u64 *raid_map)
{
struct extent_buffer *ebs[multi->num_stripes], *p_eb = NULL, *q_eb = NULL;
int i;
int j;
int ret;
int alloc_size = eb->len;
if (stripe_len > alloc_size)
alloc_size = stripe_len;
split_eb_for_raid56(info, eb, ebs, stripe_len, raid_map,
multi->num_stripes);
for (i = 0; i < multi->num_stripes; i++) {
struct extent_buffer *new_eb;
if (raid_map[i] < BTRFS_RAID5_P_STRIPE) {
ebs[i]->dev_bytenr = multi->stripes[i].physical;
ebs[i]->fd = multi->stripes[i].dev->fd;
multi->stripes[i].dev->total_ios++;
BUG_ON(ebs[i]->start != raid_map[i]);
continue;
}
new_eb = kmalloc(sizeof(*eb) + alloc_size, GFP_NOFS);
BUG_ON(!new_eb);
new_eb->dev_bytenr = multi->stripes[i].physical;
new_eb->fd = multi->stripes[i].dev->fd;
multi->stripes[i].dev->total_ios++;
new_eb->len = stripe_len;
if (raid_map[i] == BTRFS_RAID5_P_STRIPE)
p_eb = new_eb;
else if (raid_map[i] == BTRFS_RAID6_Q_STRIPE)
q_eb = new_eb;
}
if (q_eb) {
void *pointers[multi->num_stripes];
ebs[multi->num_stripes - 2] = p_eb;
ebs[multi->num_stripes - 1] = q_eb;
for (i = 0; i < multi->num_stripes; i++)
pointers[i] = ebs[i]->data;
raid6_gen_syndrome(multi->num_stripes, stripe_len, pointers);
} else {
ebs[multi->num_stripes - 1] = p_eb;
memcpy(p_eb->data, ebs[0]->data, stripe_len);
for (j = 1; j < multi->num_stripes - 1; j++) {
for (i = 0; i < stripe_len; i += sizeof(unsigned long)) {
*(unsigned long *)(p_eb->data + i) ^=
*(unsigned long *)(ebs[j]->data + i);
}
}
}
for (i = 0; i < multi->num_stripes; i++) {
ret = write_extent_to_disk(ebs[i]);
BUG_ON(ret);
if (ebs[i] != eb)
kfree(ebs[i]);
}
return 0;
}
int write_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *eb)
{
int ret;
int dev_nr;
u64 length;
u64 *raid_map = NULL;
struct btrfs_multi_bio *multi = NULL;
if (check_tree_block(root, eb))
BUG();
if (!btrfs_buffer_uptodate(eb, trans->transid))
BUG();
btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
csum_tree_block(root, eb, 0);
dev_nr = 0;
length = eb->len;
ret = btrfs_map_block(&root->fs_info->mapping_tree, WRITE,
eb->start, &length, &multi, 0, &raid_map);
if (raid_map) {
ret = write_raid56_with_parity(root->fs_info, eb, multi,
length, raid_map);
BUG_ON(ret);
} else while (dev_nr < multi->num_stripes) {
BUG_ON(ret);
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);
BUG_ON(ret);
}
kfree(multi);
return 0;
}
int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
u32 stripesize, struct btrfs_root *root,
struct btrfs_fs_info *fs_info, u64 objectid)
{
root->node = NULL;
root->commit_root = NULL;
root->sectorsize = sectorsize;
root->nodesize = nodesize;
root->leafsize = leafsize;
root->stripesize = stripesize;
root->ref_cows = 0;
root->track_dirty = 0;
root->fs_info = fs_info;
root->objectid = objectid;
root->last_trans = 0;
root->highest_inode = 0;
root->last_inode_alloc = 0;
INIT_LIST_HEAD(&root->dirty_list);
memset(&root->root_key, 0, sizeof(root->root_key));
memset(&root->root_item, 0, sizeof(root->root_item));
root->root_key.objectid = objectid;
return 0;
}
static int update_cowonly_root(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
int ret;
u64 old_root_bytenr;
struct btrfs_root *tree_root = root->fs_info->tree_root;
btrfs_write_dirty_block_groups(trans, root);
while(1) {
old_root_bytenr = btrfs_root_bytenr(&root->root_item);
if (old_root_bytenr == root->node->start)
break;
btrfs_set_root_bytenr(&root->root_item,
root->node->start);
btrfs_set_root_generation(&root->root_item,
trans->transid);
root->root_item.level = btrfs_header_level(root->node);
ret = btrfs_update_root(trans, tree_root,
&root->root_key,
&root->root_item);
BUG_ON(ret);
btrfs_write_dirty_block_groups(trans, root);
}
return 0;
}
static int commit_tree_roots(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
struct btrfs_root *root;
struct list_head *next;
struct extent_buffer *eb;
int ret;
if (fs_info->readonly)
return 0;
eb = fs_info->tree_root->node;
extent_buffer_get(eb);
ret = btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb);
free_extent_buffer(eb);
if (ret)
return ret;
while(!list_empty(&fs_info->dirty_cowonly_roots)) {
next = fs_info->dirty_cowonly_roots.next;
list_del_init(next);
root = list_entry(next, struct btrfs_root, dirty_list);
update_cowonly_root(trans, root);
}
return 0;
}
static int __commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
u64 start;
u64 end;
struct extent_buffer *eb;
struct extent_io_tree *tree = &root->fs_info->extent_cache;
int ret;
while(1) {
ret = find_first_extent_bit(tree, 0, &start, &end,
EXTENT_DIRTY);
if (ret)
break;
while(start <= end) {
eb = find_first_extent_buffer(tree, start);
BUG_ON(!eb || eb->start != start);
ret = write_tree_block(trans, root, eb);
BUG_ON(ret);
start += eb->len;
clear_extent_buffer_dirty(eb);
free_extent_buffer(eb);
}
}
return 0;
}
int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
u64 transid = trans->transid;
int ret = 0;
struct btrfs_fs_info *fs_info = root->fs_info;
if (root->commit_root == root->node)
goto commit_tree;
free_extent_buffer(root->commit_root);
root->commit_root = NULL;
btrfs_set_root_bytenr(&root->root_item, root->node->start);
btrfs_set_root_generation(&root->root_item, trans->transid);
root->root_item.level = btrfs_header_level(root->node);
ret = btrfs_update_root(trans, root->fs_info->tree_root,
&root->root_key, &root->root_item);
BUG_ON(ret);
commit_tree:
ret = commit_tree_roots(trans, fs_info);
BUG_ON(ret);
ret = __commit_transaction(trans, root);
BUG_ON(ret);
write_ctree_super(trans, root);
btrfs_finish_extent_commit(trans, fs_info->extent_root,
&fs_info->pinned_extents);
btrfs_free_transaction(root, trans);
free_extent_buffer(root->commit_root);
root->commit_root = NULL;
fs_info->running_transaction = NULL;
fs_info->last_trans_committed = transid;
return 0;
}
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;
u32 blocksize;
u64 generation;
__setup_root(tree_root->nodesize, tree_root->leafsize,
tree_root->sectorsize, tree_root->stripesize,
root, fs_info, objectid);
ret = btrfs_find_last_root(tree_root, objectid,
&root->root_item, &root->root_key);
if (ret)
return ret;
blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
generation = btrfs_root_generation(&root->root_item);
root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
blocksize, 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)
{
u32 blocksize;
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;
}
blocksize = btrfs_level_size(tree_root,
btrfs_super_log_root_level(disk_super));
__setup_root(tree_root->nodesize, tree_root->leafsize,
tree_root->sectorsize, tree_root->stripesize,
log_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
log_root->node = read_tree_block(tree_root, blocknr,
blocksize,
btrfs_super_generation(disk_super) + 1);
fs_info->log_root_tree = log_root;
if (!extent_buffer_uptodate(log_root->node)) {
free(log_root);
return -EIO;
}
free(log_root);
return 0;
}
int btrfs_free_fs_root(struct btrfs_fs_info *fs_info,
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 int free_fs_roots(struct btrfs_fs_info *fs_info)
{
struct cache_extent *cache;
struct btrfs_root *root;
while (1) {
cache = find_first_cache_extent(&fs_info->fs_root_cache, 0);
if (!cache)
break;
root = container_of(cache, struct btrfs_root, cache);
remove_cache_extent(&fs_info->fs_root_cache, cache);
btrfs_free_fs_root(fs_info, root);
}
return 0;
}
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;
u32 blocksize;
int ret = 0;
root = malloc(sizeof(*root));
if (!root)
return ERR_PTR(-ENOMEM);
memset(root, 0, sizeof(*root));
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;
}
__setup_root(tree_root->nodesize, tree_root->leafsize,
tree_root->sectorsize, tree_root->stripesize,
root, fs_info, location->objectid);
path = btrfs_alloc_path();
BUG_ON(!path);
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_release_path(root, path);
btrfs_free_path(path);
if (ret) {
free(root);
return ERR_PTR(ret);
}
generation = btrfs_root_generation(&root->root_item);
blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
blocksize, generation);
BUG_ON(!root->node);
insert:
root->ref_cows = 1;
return root;
}
struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
struct btrfs_key *location)
{
struct btrfs_root *root;
struct cache_extent *cache;
int ret;
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;
BUG_ON(location->objectid == BTRFS_TREE_RELOC_OBJECTID ||
location->offset != (u64)-1);
cache = find_cache_extent(&fs_info->fs_root_cache,
location->objectid, 1);
if (cache)
return container_of(cache, struct btrfs_root, cache);
root = btrfs_read_fs_root_no_cache(fs_info, location);
if (IS_ERR(root))
return root;
root->cache.start = location->objectid;
root->cache.size = 1;
ret = insert_existing_cache_extent(&fs_info->fs_root_cache,
&root->cache);
BUG_ON(ret);
return root;
}
static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
u64 sb_bytenr,
u64 root_tree_bytenr, int writes,
int partial)
{
u32 sectorsize;
u32 nodesize;
u32 leafsize;
u32 blocksize;
u32 stripesize;
u64 generation;
struct btrfs_key key;
struct btrfs_root *tree_root = malloc(sizeof(struct btrfs_root));
struct btrfs_root *extent_root = malloc(sizeof(struct btrfs_root));
struct btrfs_root *chunk_root = malloc(sizeof(struct btrfs_root));
struct btrfs_root *dev_root = malloc(sizeof(struct btrfs_root));
struct btrfs_root *csum_root = malloc(sizeof(struct btrfs_root));
struct btrfs_fs_info *fs_info = malloc(sizeof(*fs_info));
int ret;
struct btrfs_super_block *disk_super;
struct btrfs_fs_devices *fs_devices = NULL;
u64 total_devs;
u64 features;
if (sb_bytenr == 0)
sb_bytenr = BTRFS_SUPER_INFO_OFFSET;
/* try to drop all the caches */
posix_fadvise(fp, 0, 0, POSIX_FADV_DONTNEED);
ret = btrfs_scan_one_device(fp, path, &fs_devices,
&total_devs, sb_bytenr);
if (ret) {
fprintf(stderr, "No valid Btrfs found on %s\n", path);
goto out;
}
if (total_devs != 1) {
ret = btrfs_scan_for_fsid(fs_devices, total_devs, 1);
if (ret)
goto out;
}
memset(fs_info, 0, sizeof(*fs_info));
fs_info->tree_root = tree_root;
fs_info->extent_root = extent_root;
fs_info->chunk_root = chunk_root;
fs_info->dev_root = dev_root;
fs_info->csum_root = csum_root;
if (!writes)
fs_info->readonly = 1;
extent_io_tree_init(&fs_info->extent_cache);
extent_io_tree_init(&fs_info->free_space_cache);
extent_io_tree_init(&fs_info->block_group_cache);
extent_io_tree_init(&fs_info->pinned_extents);
extent_io_tree_init(&fs_info->pending_del);
extent_io_tree_init(&fs_info->extent_ins);
cache_tree_init(&fs_info->fs_root_cache);
cache_tree_init(&fs_info->mapping_tree.cache_tree);
mutex_init(&fs_info->fs_mutex);
fs_info->fs_devices = fs_devices;
INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
INIT_LIST_HEAD(&fs_info->space_info);
__setup_root(4096, 4096, 4096, 4096, tree_root,
fs_info, BTRFS_ROOT_TREE_OBJECTID);
if (writes)
ret = btrfs_open_devices(fs_devices, O_RDWR);
else
ret = btrfs_open_devices(fs_devices, O_RDONLY);
if (ret)
goto out_cleanup;
fs_info->super_bytenr = sb_bytenr;
disk_super = &fs_info->super_copy;
ret = btrfs_read_dev_super(fs_devices->latest_bdev,
disk_super, sb_bytenr);
if (ret) {
printk("No valid btrfs found\n");
goto out_devices;
}
memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
features = btrfs_super_incompat_flags(disk_super) &
~BTRFS_FEATURE_INCOMPAT_SUPP;
if (features) {
printk("couldn't open because of unsupported "
"option features (%Lx).\n",
(unsigned long long)features);
goto out_devices;
}
features = btrfs_super_incompat_flags(disk_super);
if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
btrfs_set_super_incompat_flags(disk_super, features);
}
features = btrfs_super_compat_ro_flags(disk_super) &
~BTRFS_FEATURE_COMPAT_RO_SUPP;
if (writes && features) {
printk("couldn't open RDWR because of unsupported "
"option features (%Lx).\n",
(unsigned long long)features);
goto out_devices;
}
nodesize = btrfs_super_nodesize(disk_super);
leafsize = btrfs_super_leafsize(disk_super);
sectorsize = btrfs_super_sectorsize(disk_super);
stripesize = btrfs_super_stripesize(disk_super);
tree_root->nodesize = nodesize;
tree_root->leafsize = leafsize;
tree_root->sectorsize = sectorsize;
tree_root->stripesize = stripesize;
ret = btrfs_read_sys_array(tree_root);
if (ret)
goto out_devices;
blocksize = btrfs_level_size(tree_root,
btrfs_super_chunk_root_level(disk_super));
generation = btrfs_super_chunk_root_generation(disk_super);
__setup_root(nodesize, leafsize, sectorsize, stripesize,
chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
chunk_root->node = read_tree_block(chunk_root,
btrfs_super_chunk_root(disk_super),
blocksize, generation);
if (!extent_buffer_uptodate(chunk_root->node)) {
printk("Couldn't read chunk root\n");
goto out_devices;
}
read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
(unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
BTRFS_UUID_SIZE);
if (!(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_METADUMP)) {
ret = btrfs_read_chunk_tree(chunk_root);
if (ret)
goto out_failed;
}
blocksize = btrfs_level_size(tree_root,
btrfs_super_root_level(disk_super));
generation = btrfs_super_generation(disk_super);
if (!root_tree_bytenr)
root_tree_bytenr = btrfs_super_root(disk_super);
tree_root->node = read_tree_block(tree_root,
root_tree_bytenr,
blocksize, generation);
if (!extent_buffer_uptodate(tree_root->node)) {
printk("Couldn't read tree root\n");
goto out_failed;
}
ret = find_and_setup_root(tree_root, fs_info,
BTRFS_EXTENT_TREE_OBJECTID, extent_root);
if (ret) {
printk("Couldn't setup extent tree\n");
goto out_failed;
}
extent_root->track_dirty = 1;
ret = find_and_setup_root(tree_root, fs_info,
BTRFS_DEV_TREE_OBJECTID, dev_root);
if (ret) {
printk("Couldn't setup device tree\n");
goto out_failed;
}
dev_root->track_dirty = 1;
ret = find_and_setup_root(tree_root, fs_info,
BTRFS_CSUM_TREE_OBJECTID, csum_root);
if (ret) {
printk("Couldn't setup csum tree\n");
if (!partial)
goto out_failed;
}
csum_root->track_dirty = 1;
find_and_setup_log_root(tree_root, fs_info, disk_super);
fs_info->generation = generation;
fs_info->last_trans_committed = generation;
btrfs_read_block_groups(fs_info->tree_root);
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 (!fs_info->fs_root)
goto out_failed;
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;
out_failed:
if (partial)
return fs_info;
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->chunk_root)
free_extent_buffer(fs_info->chunk_root->node);
out_devices:
close_all_devices(fs_info);
out_cleanup:
extent_io_tree_cleanup(&fs_info->extent_cache);
extent_io_tree_cleanup(&fs_info->free_space_cache);
extent_io_tree_cleanup(&fs_info->block_group_cache);
extent_io_tree_cleanup(&fs_info->pinned_extents);
extent_io_tree_cleanup(&fs_info->pending_del);
extent_io_tree_cleanup(&fs_info->extent_ins);
out:
free(tree_root);
free(extent_root);
free(chunk_root);
free(dev_root);
free(csum_root);
free(fs_info);
return NULL;
}
struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
u64 sb_bytenr, int writes,
int partial)
{
int fp;
struct btrfs_fs_info *info;
int flags = O_CREAT | O_RDWR;
if (!writes)
flags = O_RDONLY;
fp = open(filename, flags, 0600);
if (fp < 0) {
fprintf (stderr, "Could not open %s\n", filename);
return NULL;
}
info = __open_ctree_fd(fp, filename, sb_bytenr, 0, writes, partial);
close(fp);
return info;
}
struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr, int writes)
{
struct btrfs_fs_info *info;
info = open_ctree_fs_info(filename, sb_bytenr, writes, 0);
if (!info)
return NULL;
return info->fs_root;
}
struct btrfs_root *open_ctree_recovery(const char *filename, u64 sb_bytenr,
u64 root_tree_bytenr)
{
int fp;
struct btrfs_fs_info *info;
fp = open(filename, O_RDONLY);
if (fp < 0) {
fprintf (stderr, "Could not open %s\n", filename);
return NULL;
}
info = __open_ctree_fd(fp, filename, sb_bytenr,
root_tree_bytenr, 0, 0);
close(fp);
if (!info)
return NULL;
return info->fs_root;
}
struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
int writes)
{
struct btrfs_fs_info *info;
info = __open_ctree_fd(fp, path, sb_bytenr, 0, writes, 0);
if (!info)
return NULL;
return info->fs_root;
}
int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr)
{
u8 fsid[BTRFS_FSID_SIZE];
int fsid_is_initialized = 0;
struct btrfs_super_block buf;
int i;
int ret;
u64 transid = 0;
u64 bytenr;
if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) {
ret = pread64(fd, &buf, sizeof(buf), sb_bytenr);
if (ret < sizeof(buf))
return -1;
if (btrfs_super_bytenr(&buf) != sb_bytenr ||
buf.magic != cpu_to_le64(BTRFS_MAGIC))
return -1;
memcpy(sb, &buf, sizeof(*sb));
return 0;
}
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
ret = pread64(fd, &buf, sizeof(buf), bytenr);
if (ret < sizeof(buf))
break;
if (btrfs_super_bytenr(&buf) != bytenr )
continue;
/* if magic is NULL, the device was removed */
if (buf.magic == 0 && i == 0)
return -1;
if (buf.magic != cpu_to_le64(BTRFS_MAGIC))
continue;
if (!fsid_is_initialized) {
memcpy(fsid, buf.fsid, sizeof(fsid));
fsid_is_initialized = 1;
} else if (memcmp(fsid, buf.fsid, sizeof(fsid))) {
/*
* 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, sizeof(*sb));
transid = btrfs_super_generation(&buf);
}
}
return transid > 0 ? 0 : -1;
}
int write_dev_supers(struct btrfs_root *root, struct btrfs_super_block *sb,
struct btrfs_device *device)
{
u64 bytenr;
u32 crc;
int i, ret;
void *buf;
buf = calloc(1, BTRFS_SUPER_INFO_SIZE);
BUG_ON(!buf);
if (root->fs_info->super_bytenr != BTRFS_SUPER_INFO_OFFSET) {
btrfs_set_super_bytenr(sb, root->fs_info->super_bytenr);
crc = ~(u32)0;
crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
btrfs_csum_final(crc, (char *)&sb->csum[0]);
memcpy(buf, sb, sizeof(*sb));
ret = pwrite64(device->fd, buf, BTRFS_SUPER_INFO_SIZE,
root->fs_info->super_bytenr);
BUG_ON(ret != BTRFS_SUPER_INFO_SIZE);
goto out;
}
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);
crc = ~(u32)0;
crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
btrfs_csum_final(crc, (char *)&sb->csum[0]);
memcpy(buf, sb, sizeof(*sb));
ret = pwrite64(device->fd, buf, BTRFS_SUPER_INFO_SIZE, bytenr);
BUG_ON(ret != BTRFS_SUPER_INFO_SIZE);
}
out:
free(buf);
return 0;
}
int write_all_supers(struct btrfs_root *root)
{
struct list_head *cur;
struct list_head *head = &root->fs_info->fs_devices->devices;
struct btrfs_device *dev;
struct btrfs_super_block *sb;
struct btrfs_dev_item *dev_item;
int ret;
u64 flags;
sb = &root->fs_info->super_copy;
dev_item = &sb->dev_item;
list_for_each(cur, head) {
dev = list_entry(cur, struct btrfs_device, 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, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
flags = btrfs_super_flags(sb);
btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
ret = write_dev_supers(root, sb, dev);
BUG_ON(ret);
}
return 0;
}
int write_ctree_super(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
int ret;
struct btrfs_root *tree_root = root->fs_info->tree_root;
struct btrfs_root *chunk_root = root->fs_info->chunk_root;
if (root->fs_info->readonly)
return 0;
btrfs_set_super_generation(&root->fs_info->super_copy,
trans->transid);
btrfs_set_super_root(&root->fs_info->super_copy,
tree_root->node->start);
btrfs_set_super_root_level(&root->fs_info->super_copy,
btrfs_header_level(tree_root->node));
btrfs_set_super_chunk_root(&root->fs_info->super_copy,
chunk_root->node->start);
btrfs_set_super_chunk_root_level(&root->fs_info->super_copy,
btrfs_header_level(chunk_root->node));
btrfs_set_super_chunk_root_generation(&root->fs_info->super_copy,
btrfs_header_generation(chunk_root->node));
ret = write_all_supers(root);
if (ret)
fprintf(stderr, "failed to write new super block err %d\n", ret);
return ret;
}
static int close_all_devices(struct btrfs_fs_info *fs_info)
{
struct list_head *list;
struct list_head *next;
struct btrfs_device *device;
return 0;
list = &fs_info->fs_devices->devices;
list_for_each(next, list) {
device = list_entry(next, struct btrfs_device, dev_list);
if (device->fd) {
fsync(device->fd);
posix_fadvise(device->fd, 0, 0, POSIX_FADV_DONTNEED);
}
close(device->fd);
}
return 0;
}
int close_ctree(struct btrfs_root *root)
{
int ret;
struct btrfs_trans_handle *trans;
struct btrfs_fs_info *fs_info = root->fs_info;
if (fs_info->last_trans_committed !=
fs_info->generation) {
trans = btrfs_start_transaction(root, 1);
btrfs_commit_transaction(trans, root);
trans = btrfs_start_transaction(root, 1);
ret = commit_tree_roots(trans, fs_info);
BUG_ON(ret);
ret = __commit_transaction(trans, root);
BUG_ON(ret);
write_ctree_super(trans, root);
btrfs_free_transaction(root, trans);
}
btrfs_free_block_groups(fs_info);
free_fs_roots(fs_info);
if (fs_info->extent_root->node)
free_extent_buffer(fs_info->extent_root->node);
if (fs_info->tree_root->node)
free_extent_buffer(fs_info->tree_root->node);
if (fs_info->chunk_root->node)
free_extent_buffer(fs_info->chunk_root->node);
if (fs_info->dev_root->node)
free_extent_buffer(fs_info->dev_root->node);
if (fs_info->csum_root->node)
free_extent_buffer(fs_info->csum_root->node);
if (fs_info->log_root_tree) {
if (fs_info->log_root_tree->node)
free_extent_buffer(fs_info->log_root_tree->node);
free(fs_info->log_root_tree);
}
close_all_devices(fs_info);
extent_io_tree_cleanup(&fs_info->extent_cache);
extent_io_tree_cleanup(&fs_info->free_space_cache);
extent_io_tree_cleanup(&fs_info->block_group_cache);
extent_io_tree_cleanup(&fs_info->pinned_extents);
extent_io_tree_cleanup(&fs_info->pending_del);
extent_io_tree_cleanup(&fs_info->extent_ins);
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);
return 0;
}
int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *eb)
{
return clear_extent_buffer_dirty(eb);
}
int wait_on_tree_block_writeback(struct btrfs_root *root,
struct extent_buffer *eb)
{
return 0;
}
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->tree, buf, parent_transid, 1);
return !ret;
}
int btrfs_set_buffer_uptodate(struct extent_buffer *eb)
{
return set_extent_buffer_uptodate(eb);
}
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