btrfs-progs/convert.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 _GNU_SOURCE 1
#ifndef __CHECKER__
#include <sys/ioctl.h>
#include <sys/mount.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/acl.h>
#include <fcntl.h>
#include <unistd.h>
#include <uuid/uuid.h>
#include <linux/fs.h>
#include "kerncompat.h"
#include "ctree.h"
#include "disk-io.h"
#include "volumes.h"
#include "transaction.h"
#include "crc32c.h"
#include "utils.h"
#include <ext2fs/ext2_fs.h>
#include <ext2fs/ext2fs.h>
#include <ext2fs/ext2_ext_attr.h>
#define INO_OFFSET (BTRFS_FIRST_FREE_OBJECTID - EXT2_ROOT_INO)
#define STRIPE_LEN (64 * 1024)
#define EXT2_IMAGE_SUBVOL_OBJECTID BTRFS_FIRST_FREE_OBJECTID
/*
* Open Ext2fs in readonly mode, read block allocation bitmap and
* inode bitmap into memory.
*/
static int open_ext2fs(const char *name, ext2_filsys *ret_fs)
{
errcode_t ret;
ext2_filsys ext2_fs;
ext2_ino_t ino;
ret = ext2fs_open(name, 0, 0, 0, unix_io_manager, &ext2_fs);
if (ret) {
fprintf(stderr, "ext2fs_open: %s\n", error_message(ret));
goto fail;
}
ret = ext2fs_read_inode_bitmap(ext2_fs);
if (ret) {
fprintf(stderr, "ext2fs_read_inode_bitmap: %s\n",
error_message(ret));
goto fail;
}
ret = ext2fs_read_block_bitmap(ext2_fs);
if (ret) {
fprintf(stderr, "ext2fs_read_block_bitmap: %s\n",
error_message(ret));
goto fail;
}
/*
* search each block group for a free inode. this set up
* uninit block/inode bitmaps appropriately.
*/
ino = 1;
while (ino <= ext2_fs->super->s_inodes_count) {
ext2_ino_t foo;
ext2fs_new_inode(ext2_fs, ino, 0, NULL, &foo);
ino += EXT2_INODES_PER_GROUP(ext2_fs->super);
}
*ret_fs = ext2_fs;
return 0;
fail:
return -1;
}
static int close_ext2fs(ext2_filsys fs)
{
ext2fs_close(fs);
return 0;
}
static int ext2_alloc_block(ext2_filsys fs, u64 goal, u64 *block_ret)
{
blk_t block;
if (!ext2fs_new_block(fs, goal, NULL, &block)) {
ext2fs_fast_mark_block_bitmap(fs->block_map, block);
*block_ret = block;
return 0;
}
return -ENOSPC;
}
static int ext2_free_block(ext2_filsys fs, u64 block)
{
BUG_ON(block != (blk_t)block);
ext2fs_fast_unmark_block_bitmap(fs->block_map, block);
return 0;
}
static int cache_free_extents(struct btrfs_root *root, ext2_filsys ext2_fs)
{
int i, ret = 0;
blk_t block;
u64 bytenr;
u64 blocksize = ext2_fs->blocksize;
block = ext2_fs->super->s_first_data_block;
for (; block < ext2_fs->super->s_blocks_count; block++) {
if (ext2fs_fast_test_block_bitmap(ext2_fs->block_map, block))
continue;
bytenr = block * blocksize;
ret = set_extent_dirty(&root->fs_info->free_space_cache,
bytenr, bytenr + blocksize - 1, 0);
BUG_ON(ret);
}
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
bytenr &= ~((u64)STRIPE_LEN - 1);
if (bytenr >= blocksize * ext2_fs->super->s_blocks_count)
break;
clear_extent_dirty(&root->fs_info->free_space_cache, bytenr,
bytenr + STRIPE_LEN - 1, 0);
}
return 0;
}
static int custom_alloc_extent(struct btrfs_root *root, u64 num_bytes,
u64 hint_byte, struct btrfs_key *ins)
{
u64 start;
u64 end;
u64 last = hint_byte;
int ret;
int wrapped = 0;
struct btrfs_block_group_cache *cache;
while(1) {
ret = find_first_extent_bit(&root->fs_info->free_space_cache,
last, &start, &end, EXTENT_DIRTY);
if (ret) {
if (wrapped++ == 0) {
last = 0;
continue;
} else {
goto fail;
}
}
start = max(last, start);
last = end + 1;
if (last - start < num_bytes)
continue;
last = start + num_bytes;
if (test_range_bit(&root->fs_info->pinned_extents,
start, last - 1, EXTENT_DIRTY, 0))
continue;
cache = btrfs_lookup_block_group(root->fs_info, start);
BUG_ON(!cache);
if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM ||
last > cache->key.objectid + cache->key.offset) {
last = cache->key.objectid + cache->key.offset;
continue;
}
clear_extent_dirty(&root->fs_info->free_space_cache,
start, start + num_bytes - 1, 0);
ins->objectid = start;
ins->offset = num_bytes;
ins->type = BTRFS_EXTENT_ITEM_KEY;
return 0;
}
fail:
fprintf(stderr, "not enough free space\n");
return -ENOSPC;
}
static int intersect_with_sb(u64 bytenr, u64 num_bytes)
{
int i;
u64 offset;
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
offset = btrfs_sb_offset(i);
offset &= ~((u64)STRIPE_LEN - 1);
if (bytenr < offset + STRIPE_LEN &&
bytenr + num_bytes > offset)
return 1;
}
return 0;
}
static int custom_free_extent(struct btrfs_root *root, u64 bytenr,
u64 num_bytes)
{
return intersect_with_sb(bytenr, num_bytes);
}
struct btrfs_extent_ops extent_ops = {
.alloc_extent = custom_alloc_extent,
.free_extent = custom_free_extent,
};
struct dir_iterate_data {
struct btrfs_trans_handle *trans;
struct btrfs_root *root;
struct btrfs_inode_item *inode;
u64 objectid;
u64 index_cnt;
u64 parent;
int errcode;
};
static u8 filetype_conversion_table[EXT2_FT_MAX] = {
[EXT2_FT_UNKNOWN] = BTRFS_FT_UNKNOWN,
[EXT2_FT_REG_FILE] = BTRFS_FT_REG_FILE,
[EXT2_FT_DIR] = BTRFS_FT_DIR,
[EXT2_FT_CHRDEV] = BTRFS_FT_CHRDEV,
[EXT2_FT_BLKDEV] = BTRFS_FT_BLKDEV,
[EXT2_FT_FIFO] = BTRFS_FT_FIFO,
[EXT2_FT_SOCK] = BTRFS_FT_SOCK,
[EXT2_FT_SYMLINK] = BTRFS_FT_SYMLINK,
};
static int dir_iterate_proc(ext2_ino_t dir, int entry,
struct ext2_dir_entry *old,
int offset, int blocksize,
char *buf,void *priv_data)
{
int ret;
int file_type;
u64 objectid;
u64 inode_size;
char dotdot[] = "..";
struct btrfs_key location;
struct ext2_dir_entry_2 *dirent = (struct ext2_dir_entry_2 *)old;
struct dir_iterate_data *idata = (struct dir_iterate_data *)priv_data;
objectid = dirent->inode + INO_OFFSET;
if (!strncmp(dirent->name, dotdot, dirent->name_len)) {
if (dirent->name_len == 2) {
BUG_ON(idata->parent != 0);
idata->parent = objectid;
}
return 0;
}
if (dirent->inode < EXT2_GOOD_OLD_FIRST_INO)
return 0;
location.objectid = objectid;
location.offset = 0;
btrfs_set_key_type(&location, BTRFS_INODE_ITEM_KEY);
file_type = dirent->file_type;
BUG_ON(file_type > EXT2_FT_SYMLINK);
ret = btrfs_insert_dir_item(idata->trans, idata->root,
dirent->name, dirent->name_len,
idata->objectid, &location,
filetype_conversion_table[file_type],
idata->index_cnt);
if (ret)
goto fail;
ret = btrfs_insert_inode_ref(idata->trans, idata->root,
dirent->name, dirent->name_len,
objectid, idata->objectid,
idata->index_cnt);
if (ret)
goto fail;
idata->index_cnt++;
inode_size = btrfs_stack_inode_size(idata->inode) +
dirent->name_len * 2;
btrfs_set_stack_inode_size(idata->inode, inode_size);
return 0;
fail:
idata->errcode = ret;
return BLOCK_ABORT;
}
static int create_dir_entries(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct btrfs_inode_item *btrfs_inode,
ext2_filsys ext2_fs, ext2_ino_t ext2_ino)
{
int ret;
errcode_t err;
struct dir_iterate_data data = {
.trans = trans,
.root = root,
.inode = btrfs_inode,
.objectid = objectid,
.index_cnt = 2,
.parent = 0,
.errcode = 0,
};
err = ext2fs_dir_iterate2(ext2_fs, ext2_ino, 0, NULL,
dir_iterate_proc, &data);
if (err)
goto error;
ret = data.errcode;
if (ret == 0 && data.parent == objectid) {
ret = btrfs_insert_inode_ref(trans, root, "..", 2,
objectid, objectid, 0);
}
return ret;
error:
fprintf(stderr, "ext2fs_dir_iterate2: %s\n", error_message(err));
return -1;
}
static int read_disk_extent(struct btrfs_root *root, u64 bytenr,
u32 num_bytes, char *buffer)
{
int ret;
struct btrfs_fs_devices *fs_devs = root->fs_info->fs_devices;
ret = pread(fs_devs->latest_bdev, buffer, num_bytes, bytenr);
if (ret != num_bytes)
goto fail;
ret = 0;
fail:
if (ret > 0)
ret = -1;
return ret;
}
/*
* Record a file extent. Do all the required works, such as inserting
* file extent item, inserting extent item and backref item into extent
* tree and updating block accounting.
*/
static int record_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct btrfs_inode_item *inode,
u64 file_pos, u64 disk_bytenr,
u64 num_bytes, int checksum)
{
int ret;
struct btrfs_fs_info *info = root->fs_info;
struct btrfs_root *extent_root = info->extent_root;
struct extent_buffer *leaf;
struct btrfs_file_extent_item *fi;
struct btrfs_key ins_key;
struct btrfs_path path;
struct btrfs_extent_item extent_item;
u32 blocksize = root->sectorsize;
u64 nbytes;
u64 bytes_used;
if (disk_bytenr == 0) {
ret = btrfs_insert_file_extent(trans, root, objectid,
file_pos, disk_bytenr,
num_bytes, num_bytes);
return ret;
}
btrfs_init_path(&path);
if (checksum) {
u64 offset;
char *buffer;
ret = -ENOMEM;
buffer = malloc(blocksize);
if (!buffer)
goto fail;
for (offset = 0; offset < num_bytes; offset += blocksize) {
ret = read_disk_extent(root, disk_bytenr + offset,
blocksize, buffer);
if (ret)
break;
ret = btrfs_csum_file_block(trans,
root->fs_info->csum_root,
disk_bytenr + num_bytes,
disk_bytenr + offset,
buffer, blocksize);
if (ret)
break;
}
free(buffer);
if (ret)
goto fail;
}
ins_key.objectid = objectid;
ins_key.offset = file_pos;
btrfs_set_key_type(&ins_key, BTRFS_EXTENT_DATA_KEY);
ret = btrfs_insert_empty_item(trans, root, &path, &ins_key,
sizeof(*fi));
if (ret)
goto fail;
leaf = path.nodes[0];
fi = btrfs_item_ptr(leaf, path.slots[0],
struct btrfs_file_extent_item);
btrfs_set_file_extent_generation(leaf, fi, trans->transid);
btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG);
btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
btrfs_set_file_extent_disk_num_bytes(leaf, fi, num_bytes);
btrfs_set_file_extent_offset(leaf, fi, 0);
btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes);
btrfs_set_file_extent_compression(leaf, fi, 0);
btrfs_set_file_extent_encryption(leaf, fi, 0);
btrfs_set_file_extent_other_encoding(leaf, fi, 0);
btrfs_mark_buffer_dirty(leaf);
nbytes = btrfs_stack_inode_nbytes(inode) + num_bytes;
btrfs_set_stack_inode_nbytes(inode, nbytes);
bytes_used = btrfs_root_used(&root->root_item);
btrfs_set_root_used(&root->root_item, bytes_used + num_bytes);
ins_key.objectid = disk_bytenr;
ins_key.offset = num_bytes;
btrfs_set_key_type(&ins_key, BTRFS_EXTENT_ITEM_KEY);
btrfs_set_stack_extent_refs(&extent_item, 0);
ret = btrfs_insert_item(trans, extent_root, &ins_key,
&extent_item, sizeof(extent_item));
if (ret == 0) {
bytes_used = btrfs_super_bytes_used(&info->super_copy);
btrfs_set_super_bytes_used(&info->super_copy, bytes_used +
num_bytes);
ret = btrfs_update_block_group(trans, root, disk_bytenr,
num_bytes, 1, 0);
if (ret)
goto fail;
} else if (ret != -EEXIST) {
goto fail;
}
btrfs_extent_post_op(trans, extent_root);
ret = btrfs_inc_extent_ref(trans, root, disk_bytenr, num_bytes,
leaf->start, root->root_key.objectid,
trans->transid, objectid);
if (ret)
goto fail;
ret = 0;
fail:
btrfs_release_path(root, &path);
return ret;
}
static int record_file_blocks(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct btrfs_inode_item *inode,
u64 file_block, u64 disk_block,
u64 num_blocks, int checksum)
{
u64 file_pos = file_block * root->sectorsize;
u64 disk_bytenr = disk_block * root->sectorsize;
u64 num_bytes = num_blocks * root->sectorsize;
return record_file_extent(trans, root, objectid, inode, file_pos,
disk_bytenr, num_bytes, checksum);
}
struct blk_iterate_data {
struct btrfs_trans_handle *trans;
struct btrfs_root *root;
struct btrfs_inode_item *inode;
u64 objectid;
u64 first_block;
u64 disk_block;
u64 num_blocks;
u64 boundary;
int checksum;
int errcode;
};
static int block_iterate_proc(ext2_filsys ext2_fs,
u64 disk_block, u64 file_block,
struct blk_iterate_data *idata)
{
int ret;
int sb_region;
int do_barrier;
struct btrfs_root *root = idata->root;
struct btrfs_trans_handle *trans = idata->trans;
struct btrfs_block_group_cache *cache;
u64 bytenr = disk_block * root->sectorsize;
sb_region = intersect_with_sb(bytenr, root->sectorsize);
do_barrier = sb_region || disk_block >= idata->boundary;
if ((idata->num_blocks > 0 && do_barrier) ||
(file_block > idata->first_block + idata->num_blocks) ||
(disk_block != idata->disk_block + idata->num_blocks)) {
if (idata->num_blocks > 0) {
ret = record_file_blocks(trans, root, idata->objectid,
idata->inode, idata->first_block,
idata->disk_block, idata->num_blocks,
idata->checksum);
if (ret)
goto fail;
idata->first_block += idata->num_blocks;
idata->num_blocks = 0;
}
if (file_block > idata->first_block) {
ret = record_file_blocks(trans, root, idata->objectid,
idata->inode, idata->first_block,
0, file_block - idata->first_block,
idata->checksum);
if (ret)
goto fail;
}
if (sb_region) {
bytenr += STRIPE_LEN - 1;
bytenr &= ~((u64)STRIPE_LEN - 1);
} else {
cache = btrfs_lookup_block_group(root->fs_info, bytenr);
BUG_ON(!cache);
bytenr = cache->key.objectid + cache->key.offset;
}
idata->first_block = file_block;
idata->disk_block = disk_block;
idata->boundary = bytenr / root->sectorsize;
}
idata->num_blocks++;
return 0;
fail:
idata->errcode = ret;
return BLOCK_ABORT;
}
static int __block_iterate_proc(ext2_filsys fs, blk_t *blocknr,
e2_blkcnt_t blockcnt, blk_t ref_block,
int ref_offset, void *priv_data)
{
struct blk_iterate_data *idata;
idata = (struct blk_iterate_data *)priv_data;
return block_iterate_proc(fs, *blocknr, blockcnt, idata);
}
/*
* traverse file's data blocks, record these data blocks as file extents.
*/
static int create_file_extents(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct btrfs_inode_item *btrfs_inode,
ext2_filsys ext2_fs, ext2_ino_t ext2_ino,
int datacsum, int packing)
{
int ret;
char *buffer = NULL;
errcode_t err;
u32 last_block;
u32 sectorsize = root->sectorsize;
u64 inode_size = btrfs_stack_inode_size(btrfs_inode);
struct blk_iterate_data data = {
.trans = trans,
.root = root,
.inode = btrfs_inode,
.objectid = objectid,
.first_block = 0,
.disk_block = 0,
.num_blocks = 0,
.boundary = (u64)-1,
.checksum = datacsum,
.errcode = 0,
};
err = ext2fs_block_iterate2(ext2_fs, ext2_ino, BLOCK_FLAG_DATA_ONLY,
NULL, __block_iterate_proc, &data);
if (err)
goto error;
ret = data.errcode;
if (ret)
goto fail;
if (packing && data.first_block == 0 && data.num_blocks > 0 &&
inode_size <= BTRFS_MAX_INLINE_DATA_SIZE(root)) {
u64 num_bytes = data.num_blocks * sectorsize;
u64 disk_bytenr = data.disk_block * sectorsize;
u64 nbytes;
buffer = malloc(num_bytes);
if (!buffer)
return -ENOMEM;
ret = read_disk_extent(root, disk_bytenr, num_bytes, buffer);
if (ret)
goto fail;
if (num_bytes > inode_size)
num_bytes = inode_size;
ret = btrfs_insert_inline_extent(trans, root, objectid,
0, buffer, num_bytes);
if (ret)
goto fail;
nbytes = btrfs_stack_inode_nbytes(btrfs_inode) + num_bytes;
btrfs_set_stack_inode_nbytes(btrfs_inode, nbytes);
} else if (data.num_blocks > 0) {
ret = record_file_blocks(trans, root, objectid, btrfs_inode,
data.first_block, data.disk_block,
data.num_blocks, data.checksum);
if (ret)
goto fail;
}
data.first_block += data.num_blocks;
last_block = (inode_size + sectorsize - 1) / sectorsize;
if (last_block > data.first_block) {
ret = record_file_blocks(trans, root, objectid, btrfs_inode,
data.first_block, 0, last_block -
data.first_block, data.checksum);
}
fail:
if (buffer)
free(buffer);
return ret;
error:
fprintf(stderr, "ext2fs_block_iterate2: %s\n", error_message(err));
return -1;
}
static int create_symbol_link(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct btrfs_inode_item *btrfs_inode,
ext2_filsys ext2_fs, ext2_ino_t ext2_ino,
struct ext2_inode *ext2_inode)
{
int ret;
char *pathname;
u64 inode_size = btrfs_stack_inode_size(btrfs_inode);
if (ext2fs_inode_data_blocks(ext2_fs, ext2_inode)) {
btrfs_set_stack_inode_size(btrfs_inode, inode_size + 1);
ret = create_file_extents(trans, root, objectid, btrfs_inode,
ext2_fs, ext2_ino, 1, 1);
btrfs_set_stack_inode_size(btrfs_inode, inode_size);
return ret;
}
pathname = (char *)&(ext2_inode->i_block[0]);
BUG_ON(pathname[inode_size] != 0);
ret = btrfs_insert_inline_extent(trans, root, objectid, 0,
pathname, inode_size + 1);
btrfs_set_stack_inode_nbytes(btrfs_inode, inode_size + 1);
return ret;
}
/*
* Following xattr/acl related codes are based on codes in
* fs/ext3/xattr.c and fs/ext3/acl.c
*/
#define EXT2_XATTR_BHDR(ptr) ((struct ext2_ext_attr_header *)(ptr))
#define EXT2_XATTR_BFIRST(ptr) \
((struct ext2_ext_attr_entry *)(EXT2_XATTR_BHDR(ptr) + 1))
#define EXT2_XATTR_IHDR(inode) \
((struct ext2_ext_attr_header *) ((void *)(inode) + \
EXT2_GOOD_OLD_INODE_SIZE + (inode)->i_extra_isize))
#define EXT2_XATTR_IFIRST(inode) \
((struct ext2_ext_attr_entry *) ((void *)EXT2_XATTR_IHDR(inode) + \
sizeof(EXT2_XATTR_IHDR(inode)->h_magic)))
static int ext2_xattr_check_names(struct ext2_ext_attr_entry *entry,
const void *end)
{
struct ext2_ext_attr_entry *next;
while (!EXT2_EXT_IS_LAST_ENTRY(entry)) {
next = EXT2_EXT_ATTR_NEXT(entry);
if ((void *)next >= end)
return -EIO;
entry = next;
}
return 0;
}
static int ext2_xattr_check_block(const char *buf, size_t size)
{
int error;
struct ext2_ext_attr_header *header = EXT2_XATTR_BHDR(buf);
if (header->h_magic != EXT2_EXT_ATTR_MAGIC ||
header->h_blocks != 1)
return -EIO;
error = ext2_xattr_check_names(EXT2_XATTR_BFIRST(buf), buf + size);
return error;
}
static int ext2_xattr_check_entry(struct ext2_ext_attr_entry *entry,
size_t size)
{
size_t value_size = entry->e_value_size;
if (entry->e_value_block != 0 || value_size > size ||
entry->e_value_offs + value_size > size)
return -EIO;
return 0;
}
#define EXT2_ACL_VERSION 0x0001
typedef struct {
__le16 e_tag;
__le16 e_perm;
__le32 e_id;
} ext2_acl_entry;
typedef struct {
__le16 e_tag;
__le16 e_perm;
} ext2_acl_entry_short;
typedef struct {
__le32 a_version;
} ext2_acl_header;
static inline int ext2_acl_count(size_t size)
{
ssize_t s;
size -= sizeof(ext2_acl_header);
s = size - 4 * sizeof(ext2_acl_entry_short);
if (s < 0) {
if (size % sizeof(ext2_acl_entry_short))
return -1;
return size / sizeof(ext2_acl_entry_short);
} else {
if (s % sizeof(ext2_acl_entry))
return -1;
return s / sizeof(ext2_acl_entry) + 4;
}
}
#define ACL_EA_VERSION 0x0002
typedef struct {
__le16 e_tag;
__le16 e_perm;
__le32 e_id;
} acl_ea_entry;
typedef struct {
__le32 a_version;
acl_ea_entry a_entries[0];
} acl_ea_header;
static inline size_t acl_ea_size(int count)
{
return sizeof(acl_ea_header) + count * sizeof(acl_ea_entry);
}
static int ext2_acl_to_xattr(void *dst, const void *src,
size_t dst_size, size_t src_size)
{
int i, count;
const void *end = src + src_size;
acl_ea_header *ext_acl = (acl_ea_header *)dst;
acl_ea_entry *dst_entry = ext_acl->a_entries;
ext2_acl_entry *src_entry;
if (src_size < sizeof(ext2_acl_header))
goto fail;
if (((ext2_acl_header *)src)->a_version !=
cpu_to_le32(EXT2_ACL_VERSION))
goto fail;
src += sizeof(ext2_acl_header);
count = ext2_acl_count(src_size);
if (count <= 0)
goto fail;
BUG_ON(dst_size < acl_ea_size(count));
ext_acl->a_version = cpu_to_le32(ACL_EA_VERSION);
for (i = 0; i < count; i++, dst_entry++) {
src_entry = (ext2_acl_entry *)src;
if (src + sizeof(ext2_acl_entry_short) > end)
goto fail;
dst_entry->e_tag = src_entry->e_tag;
dst_entry->e_perm = src_entry->e_perm;
switch (le16_to_cpu(src_entry->e_tag)) {
case ACL_USER_OBJ:
case ACL_GROUP_OBJ:
case ACL_MASK:
case ACL_OTHER:
src += sizeof(ext2_acl_entry_short);
dst_entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID);
break;
case ACL_USER:
case ACL_GROUP:
src += sizeof(ext2_acl_entry);
if (src > end)
goto fail;
dst_entry->e_id = src_entry->e_id;
break;
default:
goto fail;
}
}
if (src != end)
goto fail;
return 0;
fail:
return -EINVAL;
}
static char *xattr_prefix_table[] = {
[1] = "user.",
[2] = "system.posix_acl_access",
[3] = "system.posix_acl_default",
[4] = "trusted.",
[6] = "security.",
};
static int copy_single_xattr(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct ext2_ext_attr_entry *entry,
const void *data, u32 datalen)
{
int ret = 0;
int name_len;
int name_index;
void *databuf = NULL;
char namebuf[XATTR_NAME_MAX + 1];
name_index = entry->e_name_index;
if (name_index >= ARRAY_SIZE(xattr_prefix_table) ||
xattr_prefix_table[name_index] == NULL)
return -EOPNOTSUPP;
name_len = strlen(xattr_prefix_table[name_index]) +
entry->e_name_len;
if (name_len >= sizeof(namebuf))
return -ERANGE;
if (name_index == 2 || name_index == 3) {
size_t bufsize = acl_ea_size(ext2_acl_count(datalen));
databuf = malloc(bufsize);
if (!databuf)
return -ENOMEM;
ret = ext2_acl_to_xattr(databuf, data, bufsize, datalen);
if (ret)
goto out;
data = databuf;
datalen = bufsize;
}
strcpy(namebuf, xattr_prefix_table[name_index]);
strncat(namebuf, EXT2_EXT_ATTR_NAME(entry), entry->e_name_len);
if (name_len + datalen > BTRFS_LEAF_DATA_SIZE(root) -
sizeof(struct btrfs_item) - sizeof(struct btrfs_dir_item)) {
fprintf(stderr, "skip large xattr on inode %Lu name %.*s\n",
objectid - INO_OFFSET, name_len, namebuf);
goto out;
}
ret = btrfs_insert_xattr_item(trans, root, namebuf, name_len,
data, datalen, objectid);
out:
if (databuf)
free(databuf);
return ret;
}
static int copy_extended_attrs(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct btrfs_inode_item *btrfs_inode,
ext2_filsys ext2_fs, ext2_ino_t ext2_ino)
{
int ret = 0;
int inline_ea = 0;
errcode_t err;
u32 datalen;
u32 block_size = ext2_fs->blocksize;
u32 inode_size = EXT2_INODE_SIZE(ext2_fs->super);
struct ext2_inode_large *ext2_inode;
struct ext2_ext_attr_entry *entry;
void *data;
char *buffer = NULL;
char inode_buf[EXT2_GOOD_OLD_INODE_SIZE];
if (inode_size <= EXT2_GOOD_OLD_INODE_SIZE) {
ext2_inode = (struct ext2_inode_large *)inode_buf;
} else {
ext2_inode = (struct ext2_inode_large *)malloc(inode_size);
if (!ext2_inode)
return -ENOMEM;
}
err = ext2fs_read_inode_full(ext2_fs, ext2_ino, (void *)ext2_inode,
inode_size);
if (err) {
fprintf(stderr, "ext2fs_read_inode_full: %s\n",
error_message(err));
ret = -1;
goto out;
}
if (ext2_ino > ext2_fs->super->s_first_ino &&
inode_size > EXT2_GOOD_OLD_INODE_SIZE) {
if (EXT2_GOOD_OLD_INODE_SIZE +
ext2_inode->i_extra_isize > inode_size) {
ret = -EIO;
goto out;
}
if (ext2_inode->i_extra_isize != 0 &&
EXT2_XATTR_IHDR(ext2_inode)->h_magic ==
EXT2_EXT_ATTR_MAGIC) {
inline_ea = 1;
}
}
if (inline_ea) {
int total;
void *end = (void *)ext2_inode + inode_size;
entry = EXT2_XATTR_IFIRST(ext2_inode);
total = end - (void *)entry;
ret = ext2_xattr_check_names(entry, end);
if (ret)
goto out;
while (!EXT2_EXT_IS_LAST_ENTRY(entry)) {
ret = ext2_xattr_check_entry(entry, total);
if (ret)
goto out;
data = (void *)EXT2_XATTR_IFIRST(ext2_inode) +
entry->e_value_offs;
datalen = entry->e_value_size;
ret = copy_single_xattr(trans, root, objectid,
entry, data, datalen);
if (ret)
goto out;
entry = EXT2_EXT_ATTR_NEXT(entry);
}
}
if (ext2_inode->i_file_acl == 0)
goto out;
buffer = malloc(block_size);
if (!buffer) {
ret = -ENOMEM;
goto out;
}
err = ext2fs_read_ext_attr(ext2_fs, ext2_inode->i_file_acl, buffer);
if (err) {
fprintf(stderr, "ext2fs_read_ext_attr: %s\n",
error_message(err));
ret = -1;
goto out;
}
ret = ext2_xattr_check_block(buffer, block_size);
if (ret)
goto out;
entry = EXT2_XATTR_BFIRST(buffer);
while (!EXT2_EXT_IS_LAST_ENTRY(entry)) {
ret = ext2_xattr_check_entry(entry, block_size);
if (ret)
goto out;
data = buffer + entry->e_value_offs;
datalen = entry->e_value_size;
ret = copy_single_xattr(trans, root, objectid,
entry, data, datalen);
if (ret)
goto out;
entry = EXT2_EXT_ATTR_NEXT(entry);
}
out:
if (buffer != NULL)
free(buffer);
if ((void *)ext2_inode != inode_buf)
free(ext2_inode);
return ret;
}
#define MINORBITS 20
#define MKDEV(ma, mi) (((ma) << MINORBITS) | (mi))
static inline dev_t old_decode_dev(u16 val)
{
return MKDEV((val >> 8) & 255, val & 255);
}
static inline dev_t new_decode_dev(u32 dev)
{
unsigned major = (dev & 0xfff00) >> 8;
unsigned minor = (dev & 0xff) | ((dev >> 12) & 0xfff00);
return MKDEV(major, minor);
}
static int copy_inode_item(struct btrfs_inode_item *dst,
struct ext2_inode *src, u32 blocksize)
{
btrfs_set_stack_inode_generation(dst, 1);
btrfs_set_stack_inode_size(dst, src->i_size);
btrfs_set_stack_inode_nbytes(dst, 0);
btrfs_set_stack_inode_block_group(dst, 0);
btrfs_set_stack_inode_nlink(dst, src->i_links_count);
btrfs_set_stack_inode_uid(dst, src->i_uid | (src->i_uid_high << 16));
btrfs_set_stack_inode_gid(dst, src->i_gid | (src->i_gid_high << 16));
btrfs_set_stack_inode_mode(dst, src->i_mode);
btrfs_set_stack_inode_rdev(dst, 0);
btrfs_set_stack_inode_flags(dst, 0);
btrfs_set_stack_timespec_sec(&dst->atime, src->i_atime);
btrfs_set_stack_timespec_nsec(&dst->atime, 0);
btrfs_set_stack_timespec_sec(&dst->ctime, src->i_ctime);
btrfs_set_stack_timespec_nsec(&dst->ctime, 0);
btrfs_set_stack_timespec_sec(&dst->mtime, src->i_mtime);
btrfs_set_stack_timespec_nsec(&dst->mtime, 0);
btrfs_set_stack_timespec_sec(&dst->otime, 0);
btrfs_set_stack_timespec_nsec(&dst->otime, 0);
if (S_ISDIR(src->i_mode)) {
btrfs_set_stack_inode_size(dst, 0);
btrfs_set_stack_inode_nlink(dst, 1);
}
if (S_ISREG(src->i_mode)) {
btrfs_set_stack_inode_size(dst, (u64)src->i_size_high << 32 |
(u64)src->i_size);
}
if (!S_ISREG(src->i_mode) && !S_ISDIR(src->i_mode) &&
!S_ISLNK(src->i_mode)) {
if (src->i_block[0]) {
btrfs_set_stack_inode_rdev(dst,
old_decode_dev(src->i_block[0]));
} else {
btrfs_set_stack_inode_rdev(dst,
new_decode_dev(src->i_block[1]));
}
}
return 0;
}
/*
* copy a single inode. do all the required works, such as cloning
* inode item, creating file extents and creating directory entries.
*/
static int copy_single_inode(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
ext2_filsys ext2_fs, ext2_ino_t ext2_ino,
struct ext2_inode *ext2_inode,
int datacsum, int packing, int noxattr)
{
int ret;
struct btrfs_key inode_key;
struct btrfs_inode_item btrfs_inode;
if (ext2_inode->i_links_count == 0)
return 0;
copy_inode_item(&btrfs_inode, ext2_inode, ext2_fs->blocksize);
if (!datacsum && S_ISREG(ext2_inode->i_mode)) {
u32 flags = btrfs_stack_inode_flags(&btrfs_inode) |
BTRFS_INODE_NODATASUM;
btrfs_set_stack_inode_flags(&btrfs_inode, flags);
}
switch (ext2_inode->i_mode & S_IFMT) {
case S_IFREG:
ret = create_file_extents(trans, root, objectid, &btrfs_inode,
ext2_fs, ext2_ino, datacsum, packing);
break;
case S_IFDIR:
ret = create_dir_entries(trans, root, objectid, &btrfs_inode,
ext2_fs, ext2_ino);
break;
case S_IFLNK:
ret = create_symbol_link(trans, root, objectid, &btrfs_inode,
ext2_fs, ext2_ino, ext2_inode);
break;
default:
ret = 0;
break;
}
if (ret)
return ret;
if (!noxattr) {
ret = copy_extended_attrs(trans, root, objectid, &btrfs_inode,
ext2_fs, ext2_ino);
if (ret)
return ret;
}
inode_key.objectid = objectid;
inode_key.offset = 0;
btrfs_set_key_type(&inode_key, BTRFS_INODE_ITEM_KEY);
ret = btrfs_insert_inode(trans, root, objectid, &btrfs_inode);
return ret;
}
static int copy_disk_extent(struct btrfs_root *root, u64 dst_bytenr,
u64 src_bytenr, u32 num_bytes)
{
int ret;
char *buffer;
struct btrfs_fs_devices *fs_devs = root->fs_info->fs_devices;
buffer = malloc(num_bytes);
if (!buffer)
return -ENOMEM;
ret = pread(fs_devs->latest_bdev, buffer, num_bytes, src_bytenr);
if (ret != num_bytes)
goto fail;
ret = pwrite(fs_devs->latest_bdev, buffer, num_bytes, dst_bytenr);
if (ret != num_bytes)
goto fail;
ret = 0;
fail:
free(buffer);
if (ret > 0)
ret = -1;
return ret;
}
/*
* scan ext2's inode bitmap and copy all used inode.
*/
static int copy_inodes(struct btrfs_root *root, ext2_filsys ext2_fs,
int datacsum, int packing, int noxattr)
{
int ret;
errcode_t err;
ext2_inode_scan ext2_scan;
struct ext2_inode ext2_inode;
ext2_ino_t ext2_ino;
u64 objectid;
struct btrfs_trans_handle *trans;
trans = btrfs_start_transaction(root, 1);
if (!trans)
return -ENOMEM;
err = ext2fs_open_inode_scan(ext2_fs, 0, &ext2_scan);
if (err) {
fprintf(stderr, "ext2fs_open_inode_scan: %s\n", error_message(err));
return -1;
}
while (!(err = ext2fs_get_next_inode(ext2_scan, &ext2_ino,
&ext2_inode))) {
/* no more inodes */
if (ext2_ino == 0)
break;
/* skip special inode in ext2fs */
if (ext2_ino < EXT2_GOOD_OLD_FIRST_INO &&
ext2_ino != EXT2_ROOT_INO)
continue;
objectid = ext2_ino + INO_OFFSET;
ret = copy_single_inode(trans, root,
objectid, ext2_fs, ext2_ino,
&ext2_inode, datacsum, packing,
noxattr);
if (ret)
return ret;
if (trans->blocks_used >= 4096) {
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
}
}
if (err) {
fprintf(stderr, "ext2fs_get_next_inode: %s\n", error_message(err));
return -1;
}
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
return ret;
}
/*
* Construct a range of ext2fs image file.
* scan block allocation bitmap, find all blocks used by the ext2fs
* in this range and create file extents that point to these blocks.
*
* Note: Before calling the function, no file extent points to blocks
* in this range
*/
static int create_image_file_range(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct btrfs_inode_item *inode,
u64 start_byte, u64 end_byte,
ext2_filsys ext2_fs)
{
u32 blocksize = ext2_fs->blocksize;
u32 block = start_byte / blocksize;
u32 last_block = (end_byte + blocksize - 1) / blocksize;
int ret = 0;
struct blk_iterate_data data = {
.trans = trans,
.root = root,
.inode = inode,
.objectid = objectid,
.first_block = block,
.disk_block = 0,
.num_blocks = 0,
.boundary = (u64)-1,
.checksum = 0,
.errcode = 0,
};
for (; start_byte < end_byte; block++, start_byte += blocksize) {
if (!ext2fs_fast_test_block_bitmap(ext2_fs->block_map, block))
continue;
ret = block_iterate_proc(NULL, block, block, &data);
if (ret & BLOCK_ABORT) {
ret = data.errcode;
goto fail;
}
}
if (data.num_blocks > 0) {
ret = record_file_blocks(trans, root, objectid, inode,
data.first_block, data.disk_block,
data.num_blocks, 0);
if (ret)
goto fail;
data.first_block += data.num_blocks;
}
if (last_block > data.first_block) {
ret = record_file_blocks(trans, root, objectid, inode,
data.first_block, 0, last_block -
data.first_block, 0);
if (ret)
goto fail;
}
fail:
return ret;
}
/*
* Create the ext2fs image file.
*/
static int create_ext2_image(struct btrfs_root *root, ext2_filsys ext2_fs,
const char *name)
{
int ret;
struct btrfs_key key;
struct btrfs_key location;
struct btrfs_path path;
struct btrfs_inode_item btrfs_inode;
struct btrfs_inode_item *inode_item;
struct extent_buffer *leaf;
struct btrfs_fs_info *fs_info = root->fs_info;
struct btrfs_root *extent_root = fs_info->extent_root;
struct btrfs_trans_handle *trans;
struct btrfs_extent_ref *ref_item;
u64 bytenr;
u64 num_bytes;
u64 ref_root;
u64 ref_owner;
u64 objectid;
u64 last_byte;
u64 first_free;
u64 total_bytes;
u32 sectorsize = root->sectorsize;
int file_extent;
total_bytes = btrfs_super_total_bytes(&fs_info->super_copy);
first_free = BTRFS_SUPER_INFO_OFFSET + sectorsize * 2 - 1;
first_free &= ~((u64)sectorsize - 1);
memset(&btrfs_inode, 0, sizeof(btrfs_inode));
btrfs_set_stack_inode_generation(&btrfs_inode, 1);
btrfs_set_stack_inode_size(&btrfs_inode, total_bytes);
btrfs_set_stack_inode_nlink(&btrfs_inode, 1);
btrfs_set_stack_inode_nbytes(&btrfs_inode, 0);
btrfs_set_stack_inode_mode(&btrfs_inode, S_IFREG | 0400);
btrfs_set_stack_inode_flags(&btrfs_inode, BTRFS_INODE_NODATASUM |
BTRFS_INODE_READONLY);
btrfs_init_path(&path);
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
objectid = btrfs_root_dirid(&root->root_item);
ret = btrfs_find_free_objectid(trans, root, objectid, &objectid);
if (ret)
goto fail;
/*
* copy blocks covered by extent #0 to new positions. extent #0 is
* special, we can't rely on relocate_extents_range to relocate it.
*/
for (last_byte = 0; last_byte < first_free; last_byte += sectorsize) {
ret = custom_alloc_extent(root, sectorsize, 0, &key);
if (ret)
goto fail;
ret = copy_disk_extent(root, key.objectid, last_byte,
sectorsize);
if (ret)
goto fail;
ret = record_file_extent(trans, root, objectid,
&btrfs_inode, last_byte,
key.objectid, sectorsize, 0);
if (ret)
goto fail;
}
while(1) {
key.objectid = last_byte;
key.offset = 0;
btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
ret = btrfs_search_slot(trans, fs_info->extent_root,
&key, &path, 0, 0);
if (ret < 0)
goto fail;
next:
leaf = path.nodes[0];
if (path.slots[0] >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(extent_root, &path);
if (ret < 0)
goto fail;
if (ret > 0)
break;
leaf = path.nodes[0];
}
btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
if (last_byte > key.objectid ||
key.type != BTRFS_EXTENT_ITEM_KEY) {
path.slots[0]++;
goto next;
}
/*
* Check backref to distinguish extent items for normal
* files (files that correspond to files in Ext2fs) from
* extent items for ctree blocks.
*/
bytenr = key.objectid;
num_bytes = key.offset;
file_extent = 0;
while (1) {
if (path.slots[0] >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(extent_root, &path);
if (ret > 0)
break;
if (ret < 0)
goto fail;
leaf = path.nodes[0];
}
btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
if (key.objectid != bytenr)
break;
if (key.type != BTRFS_EXTENT_REF_KEY) {
path.slots[0]++;
continue;
}
ref_item = btrfs_item_ptr(leaf, path.slots[0],
struct btrfs_extent_ref);
ref_root = btrfs_ref_root(leaf, ref_item);
ref_owner = btrfs_ref_objectid(leaf, ref_item);
if ((ref_root == BTRFS_FS_TREE_OBJECTID) &&
(ref_owner >= BTRFS_FIRST_FREE_OBJECTID)) {
file_extent = 1;
break;
}
path.slots[0]++;
}
if (!file_extent)
goto next;
if (bytenr > last_byte) {
ret = create_image_file_range(trans, root, objectid,
&btrfs_inode, last_byte,
bytenr, ext2_fs);
if (ret)
goto fail;
}
ret = record_file_extent(trans, root, objectid, &btrfs_inode,
bytenr, bytenr, num_bytes, 0);
if (ret)
goto fail;
last_byte = bytenr + num_bytes;
btrfs_release_path(extent_root, &path);
if (trans->blocks_used >= 4096) {
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
}
}
btrfs_release_path(root, &path);
if (total_bytes > last_byte) {
ret = create_image_file_range(trans, root, objectid,
&btrfs_inode, last_byte,
total_bytes, ext2_fs);
if (ret)
goto fail;
}
ret = btrfs_insert_inode(trans, root, objectid, &btrfs_inode);
if (ret)
goto fail;
location.objectid = objectid;
location.offset = 0;
btrfs_set_key_type(&location, BTRFS_INODE_ITEM_KEY);
ret = btrfs_insert_dir_item(trans, root, name, strlen(name),
btrfs_root_dirid(&root->root_item),
&location, EXT2_FT_REG_FILE, objectid);
if (ret)
goto fail;
ret = btrfs_insert_inode_ref(trans, root, name, strlen(name),
objectid,
btrfs_root_dirid(&root->root_item),
objectid);
if (ret)
goto fail;
location.objectid = btrfs_root_dirid(&root->root_item);
location.offset = 0;
btrfs_set_key_type(&location, BTRFS_INODE_ITEM_KEY);
ret = btrfs_lookup_inode(trans, root, &path, &location, 1);
if (ret)
goto fail;
leaf = path.nodes[0];
inode_item = btrfs_item_ptr(leaf, path.slots[0],
struct btrfs_inode_item);
btrfs_set_inode_size(leaf, inode_item, strlen(name) * 2 +
btrfs_inode_size(leaf, inode_item));
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(root, &path);
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
fail:
btrfs_release_path(root, &path);
return ret;
}
struct btrfs_root *link_subvol(struct btrfs_root *root, const char *base,
u64 root_objectid)
{
struct btrfs_trans_handle *trans;
struct btrfs_fs_info *fs_info = root->fs_info;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_root *new_root = NULL;
struct btrfs_path *path;
struct btrfs_inode_item *inode_item;
struct extent_buffer *leaf;
struct btrfs_key key;
u64 dirid = btrfs_root_dirid(&root->root_item);
u64 index = 2;
char buf[64];
int i;
int ret;
path = btrfs_alloc_path();
BUG_ON(!path);
key.objectid = dirid;
key.type = BTRFS_DIR_INDEX_KEY;
key.offset = (u64)-1;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
BUG_ON(ret <= 0);
if (path->slots[0] > 0) {
path->slots[0]--;
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
if (key.objectid == dirid && key.type == BTRFS_DIR_INDEX_KEY)
index = key.offset + 1;
}
btrfs_release_path(root, path);
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
key.objectid = dirid;
key.offset = 0;
key.type = BTRFS_INODE_ITEM_KEY;
ret = btrfs_lookup_inode(trans, root, path, &key, 1);
BUG_ON(ret);
leaf = path->nodes[0];
inode_item = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_inode_item);
key.objectid = root_objectid;
key.offset = (u64)-1;
key.type = BTRFS_ROOT_ITEM_KEY;
strcpy(buf, base);
for (i = 0; i < 1024; i++) {
ret = btrfs_insert_dir_item(trans, root, buf, strlen(buf),
dirid, &key, BTRFS_FT_DIR, index);
if (ret != -EEXIST)
break;
sprintf(buf, "%s%d", base, i);
}
if (ret)
goto fail;
btrfs_set_inode_size(leaf, inode_item, strlen(buf) * 2 +
btrfs_inode_size(leaf, inode_item));
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(root, path);
/* add the backref first */
ret = btrfs_add_root_ref(trans, tree_root, root_objectid,
BTRFS_ROOT_BACKREF_KEY,
root->root_key.objectid,
dirid, index, buf, strlen(buf));
BUG_ON(ret);
/* now add the forward ref */
ret = btrfs_add_root_ref(trans, tree_root, root->root_key.objectid,
BTRFS_ROOT_REF_KEY, root_objectid,
dirid, index, buf, strlen(buf));
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
new_root = btrfs_read_fs_root(fs_info, &key);
if (IS_ERR(new_root))
new_root = NULL;
fail:
btrfs_free_path(path);
return new_root;
}
/*
* Fixup block accounting. The initial block accounting created by
* make_block_groups isn't accuracy in this case.
*/
static int fixup_block_accounting(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
int ret;
int slot;
u64 start = 0;
u64 bytes_used = 0;
struct btrfs_path path;
struct btrfs_key key;
struct extent_buffer *leaf;
struct btrfs_block_group_cache *cache;
struct btrfs_fs_info *fs_info = root->fs_info;
while(1) {
cache = btrfs_lookup_block_group(fs_info, start);
if (!cache)
break;
start = cache->key.objectid + cache->key.offset;
btrfs_set_block_group_used(&cache->item, 0);
cache->space_info->bytes_used = 0;
}
btrfs_init_path(&path);
key.offset = 0;
key.objectid = 0;
btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
ret = btrfs_search_slot(trans, root->fs_info->extent_root,
&key, &path, 0, 0);
if (ret < 0)
return ret;
while(1) {
leaf = path.nodes[0];
slot = path.slots[0];
if (slot >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(root, &path);
if (ret < 0)
return ret;
if (ret > 0)
break;
leaf = path.nodes[0];
slot = path.slots[0];
}
btrfs_item_key_to_cpu(leaf, &key, slot);
if (key.type == BTRFS_EXTENT_ITEM_KEY) {
bytes_used += key.offset;
ret = btrfs_update_block_group(trans, root,
key.objectid, key.offset, 1, 0);
BUG_ON(ret);
}
path.slots[0]++;
}
btrfs_set_super_bytes_used(&root->fs_info->super_copy, bytes_used);
btrfs_release_path(root, &path);
return 0;
}
static int create_chunk_mapping(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
struct btrfs_fs_info *info = root->fs_info;
struct btrfs_root *chunk_root = info->chunk_root;
struct btrfs_root *extent_root = info->extent_root;
struct btrfs_device *device;
struct btrfs_block_group_cache *cache;
struct btrfs_dev_extent *extent;
struct extent_buffer *leaf;
struct btrfs_chunk chunk;
struct btrfs_key key;
struct btrfs_path path;
u64 cur_start;
u64 total_bytes;
u64 chunk_objectid;
int ret;
btrfs_init_path(&path);
total_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
BUG_ON(list_empty(&info->fs_devices->devices));
device = list_entry(info->fs_devices->devices.next,
struct btrfs_device, dev_list);
BUG_ON(device->devid != info->fs_devices->latest_devid);
/* delete device extent created by make_btrfs */
key.objectid = device->devid;
key.offset = 0;
key.type = BTRFS_DEV_EXTENT_KEY;
ret = btrfs_search_slot(trans, device->dev_root, &key, &path, -1, 1);
if (ret < 0)
goto err;
BUG_ON(ret > 0);
ret = btrfs_del_item(trans, device->dev_root, &path);
if (ret)
goto err;
btrfs_release_path(device->dev_root, &path);
/* delete chunk item created by make_btrfs */
key.objectid = chunk_objectid;
key.offset = 0;
key.type = BTRFS_CHUNK_ITEM_KEY;
ret = btrfs_search_slot(trans, chunk_root, &key, &path, -1, 1);
if (ret < 0)
goto err;
BUG_ON(ret > 0);
ret = btrfs_del_item(trans, chunk_root, &path);
if (ret)
goto err;
btrfs_release_path(chunk_root, &path);
/* for each block group, create device extent and chunk item */
cur_start = 0;
while (cur_start < total_bytes) {
cache = btrfs_lookup_block_group(root->fs_info, cur_start);
BUG_ON(!cache);
/* insert device extent */
key.objectid = device->devid;
key.offset = cache->key.objectid;
key.type = BTRFS_DEV_EXTENT_KEY;
ret = btrfs_insert_empty_item(trans, device->dev_root, &path,
&key, sizeof(*extent));
if (ret)
goto err;
leaf = path.nodes[0];
extent = btrfs_item_ptr(leaf, path.slots[0],
struct btrfs_dev_extent);
btrfs_set_dev_extent_chunk_tree(leaf, extent,
chunk_root->root_key.objectid);
btrfs_set_dev_extent_chunk_objectid(leaf, extent,
chunk_objectid);
btrfs_set_dev_extent_chunk_offset(leaf, extent,
cache->key.objectid);
btrfs_set_dev_extent_length(leaf, extent, cache->key.offset);
write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
(unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent),
BTRFS_UUID_SIZE);
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(device->dev_root, &path);
/* insert chunk item */
btrfs_set_stack_chunk_length(&chunk, cache->key.offset);
btrfs_set_stack_chunk_owner(&chunk,
extent_root->root_key.objectid);
btrfs_set_stack_chunk_stripe_len(&chunk, STRIPE_LEN);
btrfs_set_stack_chunk_type(&chunk, cache->flags);
btrfs_set_stack_chunk_io_align(&chunk, device->io_align);
btrfs_set_stack_chunk_io_width(&chunk, device->io_width);
btrfs_set_stack_chunk_sector_size(&chunk, device->sector_size);
btrfs_set_stack_chunk_num_stripes(&chunk, 1);
btrfs_set_stack_chunk_sub_stripes(&chunk, 0);
btrfs_set_stack_stripe_devid(&chunk.stripe, device->devid);
btrfs_set_stack_stripe_offset(&chunk.stripe,
cache->key.objectid);
memcpy(&chunk.stripe.dev_uuid, device->uuid, BTRFS_UUID_SIZE);
key.objectid = chunk_objectid;
key.offset = cache->key.objectid;
key.type = BTRFS_CHUNK_ITEM_KEY;
ret = btrfs_insert_item(trans, chunk_root, &key, &chunk,
btrfs_chunk_item_size(1));
if (ret)
goto err;
cur_start = cache->key.objectid + cache->key.offset;
}
device->bytes_used = total_bytes;
ret = btrfs_update_device(trans, device);
err:
btrfs_release_path(device->dev_root, &path);
return ret;
}
static int create_subvol(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 root_objectid)
{
struct extent_buffer *tmp;
struct btrfs_root *new_root;
struct btrfs_key key;
struct btrfs_root_item root_item;
int ret;
ret = btrfs_copy_root(trans, root, root->node, &tmp,
root_objectid);
BUG_ON(ret);
memcpy(&root_item, &root->root_item, sizeof(root_item));
btrfs_set_root_bytenr(&root_item, tmp->start);
btrfs_set_root_level(&root_item, btrfs_header_level(tmp));
btrfs_set_root_generation(&root_item, trans->transid);
free_extent_buffer(tmp);
key.objectid = root_objectid;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = trans->transid;
ret = btrfs_insert_root(trans, root->fs_info->tree_root,
&key, &root_item);
key.offset = (u64)-1;
new_root = btrfs_read_fs_root(root->fs_info, &key);
BUG_ON(!new_root || IS_ERR(new_root));
ret = btrfs_make_root_dir(trans, new_root, BTRFS_FIRST_FREE_OBJECTID);
BUG_ON(ret);
btrfs_free_fs_root(root->fs_info, new_root);
return 0;
}
static int init_btrfs(struct btrfs_root *root)
{
int ret;
struct btrfs_key location;
struct btrfs_trans_handle *trans;
struct btrfs_fs_info *fs_info = root->fs_info;
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
ret = btrfs_make_block_groups(trans, root);
if (ret)
goto err;
ret = fixup_block_accounting(trans, root);
if (ret)
goto err;
ret = create_chunk_mapping(trans, root);
if (ret)
goto err;
ret = btrfs_make_root_dir(trans, fs_info->tree_root,
BTRFS_ROOT_TREE_DIR_OBJECTID);
if (ret)
goto err;
memcpy(&location, &root->root_key, sizeof(location));
location.offset = (u64)-1;
ret = btrfs_insert_dir_item(trans, fs_info->tree_root, "default", 7,
btrfs_super_root_dir(&fs_info->super_copy),
&location, BTRFS_FT_DIR, 0);
if (ret)
goto err;
ret = btrfs_insert_inode_ref(trans, fs_info->tree_root, "default", 7,
location.objectid,
btrfs_super_root_dir(&fs_info->super_copy), 0);
if (ret)
goto err;
btrfs_set_root_dirid(&fs_info->fs_root->root_item,
BTRFS_FIRST_FREE_OBJECTID);
/* subvol for ext2 image file */
ret = create_subvol(trans, root, EXT2_IMAGE_SUBVOL_OBJECTID);
BUG_ON(ret);
/* subvol for data relocation */
ret = create_subvol(trans, root, BTRFS_DATA_RELOC_TREE_OBJECTID);
BUG_ON(ret);
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
err:
return ret;
}
/*
* Migrate super block to it's default position and zero 0 ~ 16k
*/
static int migrate_super_block(int fd, u64 old_bytenr, u32 sectorsize)
{
int ret;
struct extent_buffer *buf;
struct btrfs_super_block *super;
u32 len;
u32 bytenr;
BUG_ON(sectorsize < sizeof(*super));
buf = malloc(sizeof(*buf) + sectorsize);
if (!buf)
return -ENOMEM;
buf->len = sectorsize;
ret = pread(fd, buf->data, sectorsize, old_bytenr);
if (ret != sectorsize)
goto fail;
super = (struct btrfs_super_block *)buf->data;
BUG_ON(btrfs_super_bytenr(super) != old_bytenr);
btrfs_set_super_bytenr(super, BTRFS_SUPER_INFO_OFFSET);
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, sectorsize, BTRFS_SUPER_INFO_OFFSET);
if (ret != sectorsize)
goto fail;
ret = fsync(fd);
if (ret)
goto fail;
memset(buf->data, 0, sectorsize);
for (bytenr = 0; bytenr < BTRFS_SUPER_INFO_OFFSET; ) {
len = BTRFS_SUPER_INFO_OFFSET - bytenr;
if (len > sectorsize)
len = sectorsize;
ret = pwrite(fd, buf->data, len, bytenr);
if (ret != len) {
fprintf(stderr, "unable to zero fill device\n");
break;
}
bytenr += len;
}
ret = 0;
fsync(fd);
fail:
free(buf);
if (ret > 0)
ret = -1;
return ret;
}
static int prepare_system_chunk_sb(struct btrfs_super_block *super)
{
struct btrfs_chunk *chunk;
struct btrfs_disk_key *key;
u32 sectorsize = btrfs_super_sectorsize(super);
key = (struct btrfs_disk_key *)(super->sys_chunk_array);
chunk = (struct btrfs_chunk *)(super->sys_chunk_array +
sizeof(struct btrfs_disk_key));
btrfs_set_disk_key_objectid(key, BTRFS_FIRST_CHUNK_TREE_OBJECTID);
btrfs_set_disk_key_type(key, BTRFS_CHUNK_ITEM_KEY);
btrfs_set_disk_key_offset(key, 0);
btrfs_set_stack_chunk_length(chunk, btrfs_super_total_bytes(super));
btrfs_set_stack_chunk_owner(chunk, BTRFS_EXTENT_TREE_OBJECTID);
btrfs_set_stack_chunk_stripe_len(chunk, 64 * 1024);
btrfs_set_stack_chunk_type(chunk, BTRFS_BLOCK_GROUP_SYSTEM);
btrfs_set_stack_chunk_io_align(chunk, sectorsize);
btrfs_set_stack_chunk_io_width(chunk, sectorsize);
btrfs_set_stack_chunk_sector_size(chunk, sectorsize);
btrfs_set_stack_chunk_num_stripes(chunk, 1);
btrfs_set_stack_chunk_sub_stripes(chunk, 0);
chunk->stripe.devid = super->dev_item.devid;
chunk->stripe.offset = cpu_to_le64(0);
memcpy(chunk->stripe.dev_uuid, super->dev_item.uuid, BTRFS_UUID_SIZE);
btrfs_set_super_sys_array_size(super, sizeof(*key) + sizeof(*chunk));
return 0;
}
static int prepare_system_chunk(int fd, u64 sb_bytenr, u32 sectorsize)
{
int ret;
struct extent_buffer *buf;
struct btrfs_super_block *super;
BUG_ON(sectorsize < sizeof(*super));
buf = malloc(sizeof(*buf) + sectorsize);
if (!buf)
return -ENOMEM;
buf->len = sectorsize;
ret = pread(fd, buf->data, sectorsize, sb_bytenr);
if (ret != sectorsize)
goto fail;
super = (struct btrfs_super_block *)buf->data;
BUG_ON(btrfs_super_bytenr(super) != sb_bytenr);
BUG_ON(btrfs_super_num_devices(super) != 1);
ret = prepare_system_chunk_sb(super);
if (ret)
goto fail;
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, sectorsize, sb_bytenr);
if (ret != sectorsize)
goto fail;
ret = 0;
fail:
free(buf);
if (ret > 0)
ret = -1;
return ret;
}
static int relocate_one_reference(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 extent_start, u64 extent_size,
u64 objectid, struct btrfs_key *leaf_key,
struct extent_io_tree *reloc_tree)
{
struct extent_buffer *leaf;
struct btrfs_file_extent_item *fi;
struct btrfs_key key;
struct btrfs_path path;
struct btrfs_inode_item inode;
struct blk_iterate_data data;
u64 bytenr;
u64 offset;
u64 num_bytes;
u64 cur_offset;
u64 new_pos;
u64 nbytes;
u64 root_gen;
u64 root_owner;
u64 sector_end;
u32 nritems;
u32 sectorsize = root->sectorsize;
unsigned long ptr;
int found = 0;
int datacsum;
int fd;
int ret;
memcpy(&key, leaf_key, sizeof(key));
if (key.objectid < objectid ||
(key.objectid == objectid &&
key.type < BTRFS_EXTENT_DATA_KEY)) {
key.objectid = objectid;
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = 0;
}
btrfs_init_path(&path);
recow:
ret = btrfs_search_slot(trans, root, &key, &path, -1, 1);
if (ret < 0)
goto fail;
leaf = path.nodes[0];
nritems = btrfs_header_nritems(leaf);
while (1) {
if (path.slots[0] >= nritems) {
ret = btrfs_next_leaf(root, &path);
if (ret < 0)
goto fail;
if (ret > 0)
break;
btrfs_item_key_to_cpu(path.nodes[0], &key,
path.slots[0]);
btrfs_release_path(root, &path);
goto recow;
}
btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
if (key.objectid != objectid ||
key.type != BTRFS_EXTENT_DATA_KEY)
break;
fi = btrfs_item_ptr(leaf, path.slots[0],
struct btrfs_file_extent_item);
if (extent_start == btrfs_file_extent_disk_bytenr(leaf, fi) &&
extent_size == btrfs_file_extent_disk_num_bytes(leaf, fi)) {
offset = key.offset;
found = 1;
break;
}
path.slots[0]++;
}
if (!found) {
ret = 1;
goto fail;
}
root_gen = btrfs_header_generation(leaf);
root_owner = btrfs_header_owner(leaf);
bytenr = extent_start + btrfs_file_extent_offset(leaf, fi);
num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
ret = btrfs_del_item(trans, root, &path);
if (ret)
goto fail;
ret = btrfs_free_extent(trans, root,
extent_start, extent_size, leaf->start,
root_owner, root_gen, objectid, 0);
if (ret)
goto fail;
btrfs_release_path(root, &path);
key.objectid = objectid;
key.offset = 0;
key.type = BTRFS_INODE_ITEM_KEY;
ret = btrfs_lookup_inode(trans, root, &path, &key, 0);
if (ret)
goto fail;
leaf = path.nodes[0];
ptr = btrfs_item_ptr_offset(leaf, path.slots[0]);
read_extent_buffer(leaf, &inode, ptr, sizeof(inode));
btrfs_release_path(root, &path);
BUG_ON(num_bytes & (sectorsize - 1));
nbytes = btrfs_stack_inode_nbytes(&inode) - num_bytes;
btrfs_set_stack_inode_nbytes(&inode, nbytes);
datacsum = !(btrfs_stack_inode_flags(&inode) & BTRFS_INODE_NODATASUM);
data = (struct blk_iterate_data) {
.trans = trans,
.root = root,
.inode = &inode,
.objectid = objectid,
.first_block = offset / sectorsize,
.disk_block = 0,
.num_blocks = 0,
.boundary = (u64)-1,
.checksum = datacsum,
.errcode = 0,
};
cur_offset = offset;
while (num_bytes > 0) {
sector_end = bytenr + sectorsize - 1;
if (test_range_bit(reloc_tree, bytenr, sector_end,
EXTENT_LOCKED, 1)) {
ret = get_state_private(reloc_tree, bytenr, &new_pos);
BUG_ON(ret);
} else {
ret = custom_alloc_extent(root, sectorsize, 0, &key);
if (ret)
goto fail;
new_pos = key.objectid;
if (cur_offset == offset) {
fd = root->fs_info->fs_devices->latest_bdev;
readahead(fd, bytenr, num_bytes);
}
ret = copy_disk_extent(root, new_pos, bytenr,
sectorsize);
if (ret)
goto fail;
ret = set_extent_bits(reloc_tree, bytenr, sector_end,
EXTENT_LOCKED, GFP_NOFS);
BUG_ON(ret);
ret = set_state_private(reloc_tree, bytenr, new_pos);
BUG_ON(ret);
}
ret = block_iterate_proc(NULL, new_pos / sectorsize,
cur_offset / sectorsize, &data);
if (ret & BLOCK_ABORT) {
ret = data.errcode;
goto fail;
}
cur_offset += sectorsize;
bytenr += sectorsize;
num_bytes -= sectorsize;
}
if (data.num_blocks > 0) {
ret = record_file_blocks(trans, root, objectid, &inode,
data.first_block, data.disk_block,
data.num_blocks, datacsum);
if (ret)
goto fail;
}
key.objectid = objectid;
key.offset = 0;
key.type = BTRFS_INODE_ITEM_KEY;
ret = btrfs_lookup_inode(trans, root, &path, &key, 1);
if (ret)
goto fail;
leaf = path.nodes[0];
ptr = btrfs_item_ptr_offset(leaf, path.slots[0]);
write_extent_buffer(leaf, &inode, ptr, sizeof(inode));
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(root, &path);
fail:
btrfs_release_path(root, &path);
return ret;
}
static int relocate_extents_range(struct btrfs_root *fs_root,
struct btrfs_root *ext2_root,
u64 start_byte, u64 end_byte)
{
struct btrfs_fs_info *info = fs_root->fs_info;
struct btrfs_root *extent_root = info->extent_root;
struct btrfs_root *cur_root = NULL;
struct btrfs_trans_handle *trans;
struct btrfs_extent_ref *ref_item;
struct extent_buffer *leaf;
struct btrfs_key key;
struct btrfs_key leaf_key;
struct btrfs_path path;
struct extent_io_tree reloc_tree;
u64 cur_byte;
u64 num_bytes;
u64 ref_root;
u64 ref_owner;
u64 num_refs;
u64 leaf_start;
int pass = 0;
int ret;
int found;
btrfs_init_path(&path);
extent_io_tree_init(&reloc_tree);
key.objectid = start_byte;
key.offset = 0;
key.type = BTRFS_EXTENT_ITEM_KEY;
ret = btrfs_search_slot(NULL, extent_root, &key, &path, 0, 0);
if (ret < 0)
goto fail;
if (ret > 0) {
ret = btrfs_previous_item(extent_root, &path, 0,
BTRFS_EXTENT_ITEM_KEY);
if (ret < 0)
goto fail;
if (ret == 0) {
leaf = path.nodes[0];
btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
if (key.objectid + key.offset > start_byte)
start_byte = key.objectid;
}
}
btrfs_release_path(extent_root, &path);
again:
cur_root = (pass % 2 == 0) ? ext2_root : fs_root;
num_refs = 0;
trans = btrfs_start_transaction(cur_root, 1);
BUG_ON(!trans);
cur_byte = start_byte;
while (1) {
key.objectid = cur_byte;
key.offset = 0;
key.type = BTRFS_EXTENT_ITEM_KEY;
ret = btrfs_search_slot(trans, extent_root,
&key, &path, 0, 0);
if (ret < 0)
goto fail;
next:
leaf = path.nodes[0];
if (path.slots[0] >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(extent_root, &path);
if (ret < 0)
goto fail;
if (ret > 0)
break;
leaf = path.nodes[0];
}
btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
if (key.objectid < cur_byte ||
key.type != BTRFS_EXTENT_ITEM_KEY) {
path.slots[0]++;
goto next;
}
if (key.objectid >= end_byte)
break;
cur_byte = key.objectid;
num_bytes = key.offset;
found = 0;
while (1) {
if (path.slots[0] >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(extent_root, &path);
if (ret > 0)
break;
if (ret < 0)
goto fail;
leaf = path.nodes[0];
}
btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
if (key.objectid != cur_byte)
break;
if (key.type != BTRFS_EXTENT_REF_KEY) {
path.slots[0]++;
continue;
}
ref_item = btrfs_item_ptr(leaf, path.slots[0],
struct btrfs_extent_ref);
ref_root = btrfs_ref_root(leaf, ref_item);
ref_owner = btrfs_ref_objectid(leaf, ref_item);
leaf_start = key.offset;
num_refs++;
BUG_ON(ref_owner < BTRFS_FIRST_FREE_OBJECTID);
if (ref_root == cur_root->root_key.objectid) {
found = 1;
break;
}
path.slots[0]++;
}
if (!found)
goto next;
leaf = read_tree_block(cur_root, leaf_start,
btrfs_level_size(cur_root, 0), 0);
BUG_ON(!leaf);
BUG_ON(btrfs_header_level(leaf) != 0);
btrfs_item_key_to_cpu(leaf, &leaf_key, 0);
free_extent_buffer(leaf);
ret = relocate_one_reference(trans, cur_root, cur_byte,
num_bytes, ref_owner,
&leaf_key, &reloc_tree);
if (ret < 0)
goto fail;
cur_byte += num_bytes;
btrfs_release_path(extent_root, &path);
if (trans->blocks_used >= 4096) {
ret = btrfs_commit_transaction(trans, cur_root);
BUG_ON(ret);
trans = btrfs_start_transaction(cur_root, 1);
BUG_ON(!trans);
}
}
btrfs_release_path(cur_root, &path);
ret = btrfs_commit_transaction(trans, cur_root);
BUG_ON(ret);
if (num_refs > 0 && pass++ < 16)
goto again;
ret = (num_refs > 0) ? -1 : 0;
fail:
btrfs_release_path(cur_root, &path);
extent_io_tree_cleanup(&reloc_tree);
return ret;
}
/*
* relocate data in system chunk
*/
static int cleanup_sys_chunk(struct btrfs_root *fs_root,
struct btrfs_root *ext2_root)
{
struct btrfs_block_group_cache *cache;
int i, ret = 0;
u64 offset = 0;
u64 end_byte;
while(1) {
cache = btrfs_lookup_block_group(fs_root->fs_info, offset);
if (!cache)
break;
end_byte = cache->key.objectid + cache->key.offset;
if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
ret = relocate_extents_range(fs_root, ext2_root,
cache->key.objectid,
end_byte);
if (ret)
goto fail;
}
offset = end_byte;
}
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
offset = btrfs_sb_offset(i);
offset &= ~((u64)STRIPE_LEN - 1);
ret = relocate_extents_range(fs_root, ext2_root,
offset, offset + STRIPE_LEN);
if (ret)
goto fail;
}
ret = 0;
fail:
return ret;
}
static int fixup_chunk_mapping(struct btrfs_root *root)
{
struct btrfs_trans_handle *trans;
struct btrfs_fs_info *info = root->fs_info;
struct btrfs_root *chunk_root = info->chunk_root;
struct extent_buffer *leaf;
struct btrfs_key key;
struct btrfs_path path;
struct btrfs_chunk chunk;
unsigned long ptr;
u32 size;
u64 type;
int ret;
btrfs_init_path(&path);
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
/*
* recow the whole chunk tree. this will move all chunk tree blocks
* into system block group.
*/
memset(&key, 0, sizeof(key));
while (1) {
ret = btrfs_search_slot(trans, chunk_root, &key, &path, 0, 1);
if (ret < 0)
goto err;
ret = btrfs_next_leaf(chunk_root, &path);
if (ret < 0)
goto err;
if (ret > 0)
break;
btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
btrfs_release_path(chunk_root, &path);
}
btrfs_release_path(chunk_root, &path);
/* fixup the system chunk array in super block */
btrfs_set_super_sys_array_size(&info->super_copy, 0);
key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
key.offset = 0;
key.type = BTRFS_CHUNK_ITEM_KEY;
ret = btrfs_search_slot(trans, chunk_root, &key, &path, 0, 0);
if (ret < 0)
goto err;
BUG_ON(ret != 0);
while(1) {
leaf = path.nodes[0];
if (path.slots[0] >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(chunk_root, &path);
if (ret < 0)
goto err;
if (ret > 0)
break;
leaf = path.nodes[0];
}
btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
if (key.type != BTRFS_CHUNK_ITEM_KEY)
goto next;
ptr = btrfs_item_ptr_offset(leaf, path.slots[0]);
size = btrfs_item_size_nr(leaf, path.slots[0]);
BUG_ON(size != sizeof(chunk));
read_extent_buffer(leaf, &chunk, ptr, size);
type = btrfs_stack_chunk_type(&chunk);
if (!(type & BTRFS_BLOCK_GROUP_SYSTEM))
goto next;
ret = btrfs_add_system_chunk(trans, chunk_root, &key,
&chunk, size);
if (ret)
goto err;
next:
path.slots[0]++;
}
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
err:
btrfs_release_path(chunk_root, &path);
return ret;
}
int do_convert(const char *devname, int datacsum, int packing, int noxattr)
{
int i, fd, ret;
u32 blocksize;
Btrfs: move data checksumming into a dedicated tree Btrfs stores checksums for each data block. Until now, they have been stored in the subvolume trees, indexed by the inode that is referencing the data block. This means that when we read the inode, we've probably read in at least some checksums as well. But, this has a few problems: * The checksums are indexed by logical offset in the file. When compression is on, this means we have to do the expensive checksumming on the uncompressed data. It would be faster if we could checksum the compressed data instead. * If we implement encryption, we'll be checksumming the plain text and storing that on disk. This is significantly less secure. * For either compression or encryption, we have to get the plain text back before we can verify the checksum as correct. This makes the raid layer balancing and extent moving much more expensive. * It makes the front end caching code more complex, as we have touch the subvolume and inodes as we cache extents. * There is potentitally one copy of the checksum in each subvolume referencing an extent. The solution used here is to store the extent checksums in a dedicated tree. This allows us to index the checksums by phyiscal extent start and length. It means: * The checksum is against the data stored on disk, after any compression or encryption is done. * The checksum is stored in a central location, and can be verified without following back references, or reading inodes. This makes compression significantly faster by reducing the amount of data that needs to be checksummed. It will also allow much faster raid management code in general. The checksums are indexed by a key with a fixed objectid (a magic value in ctree.h) and offset set to the starting byte of the extent. This allows us to copy the checksum items into the fsync log tree directly (or any other tree), without having to invent a second format for them. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-12-08 22:00:31 +00:00
u64 blocks[7];
u64 total_bytes;
u64 super_bytenr;
ext2_filsys ext2_fs;
struct btrfs_root *root;
struct btrfs_root *ext2_root;
ret = open_ext2fs(devname, &ext2_fs);
if (ret) {
fprintf(stderr, "unable to open the Ext2fs\n");
goto fail;
}
blocksize = ext2_fs->blocksize;
total_bytes = (u64)ext2_fs->super->s_blocks_count * blocksize;
if (blocksize < 4096) {
fprintf(stderr, "block size is too small\n");
goto fail;
}
if (!(ext2_fs->super->s_feature_incompat &
EXT2_FEATURE_INCOMPAT_FILETYPE)) {
fprintf(stderr, "filetype feature is missing\n");
goto fail;
}
Btrfs: move data checksumming into a dedicated tree Btrfs stores checksums for each data block. Until now, they have been stored in the subvolume trees, indexed by the inode that is referencing the data block. This means that when we read the inode, we've probably read in at least some checksums as well. But, this has a few problems: * The checksums are indexed by logical offset in the file. When compression is on, this means we have to do the expensive checksumming on the uncompressed data. It would be faster if we could checksum the compressed data instead. * If we implement encryption, we'll be checksumming the plain text and storing that on disk. This is significantly less secure. * For either compression or encryption, we have to get the plain text back before we can verify the checksum as correct. This makes the raid layer balancing and extent moving much more expensive. * It makes the front end caching code more complex, as we have touch the subvolume and inodes as we cache extents. * There is potentitally one copy of the checksum in each subvolume referencing an extent. The solution used here is to store the extent checksums in a dedicated tree. This allows us to index the checksums by phyiscal extent start and length. It means: * The checksum is against the data stored on disk, after any compression or encryption is done. * The checksum is stored in a central location, and can be verified without following back references, or reading inodes. This makes compression significantly faster by reducing the amount of data that needs to be checksummed. It will also allow much faster raid management code in general. The checksums are indexed by a key with a fixed objectid (a magic value in ctree.h) and offset set to the starting byte of the extent. This allows us to copy the checksum items into the fsync log tree directly (or any other tree), without having to invent a second format for them. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-12-08 22:00:31 +00:00
for (i = 0; i < 7; i++) {
ret = ext2_alloc_block(ext2_fs, 0, blocks + i);
if (ret) {
fprintf(stderr, "not enough free space\n");
goto fail;
}
blocks[i] *= blocksize;
}
super_bytenr = blocks[0];
fd = open(devname, O_RDWR);
if (fd < 0) {
fprintf(stderr, "unable to open %s\n", devname);
goto fail;
}
ret = make_btrfs(fd, devname, ext2_fs->super->s_volume_name,
blocks, total_bytes, blocksize, blocksize,
blocksize, blocksize);
if (ret) {
fprintf(stderr, "unable to create initial ctree\n");
goto fail;
}
/* create a system chunk that maps the whole device */
ret = prepare_system_chunk(fd, super_bytenr, blocksize);
if (ret) {
fprintf(stderr, "unable to update system chunk\n");
goto fail;
}
root = open_ctree_fd(fd, devname, super_bytenr, O_RDWR);
if (!root) {
fprintf(stderr, "unable to open ctree\n");
goto fail;
}
ret = cache_free_extents(root, ext2_fs);
if (ret) {
fprintf(stderr, "error during cache_free_extents %d\n", ret);
goto fail;
}
root->fs_info->extent_ops = &extent_ops;
/* recover block allocation bitmap */
for (i = 0; i < 7; i++) {
blocks[i] /= blocksize;
ext2_free_block(ext2_fs, blocks[i]);
}
ret = init_btrfs(root);
if (ret) {
fprintf(stderr, "unable to setup the root tree\n");
goto fail;
}
printf("creating btrfs metadata.\n");
ret = copy_inodes(root, ext2_fs, datacsum, packing, noxattr);
if (ret) {
fprintf(stderr, "error during copy_inodes %d\n", ret);
goto fail;
}
printf("creating ext2fs image file.\n");
ext2_root = link_subvol(root, "ext2_saved", EXT2_IMAGE_SUBVOL_OBJECTID);
if (!ext2_root) {
fprintf(stderr, "unable to create subvol\n");
goto fail;
}
ret = create_ext2_image(ext2_root, ext2_fs, "image");
if (ret) {
fprintf(stderr, "error during create_ext2_image %d\n", ret);
goto fail;
}
printf("cleaning up system chunk.\n");
ret = cleanup_sys_chunk(root, ext2_root);
if (ret) {
fprintf(stderr, "error during cleanup_sys_chunk %d\n", ret);
goto fail;
}
btrfs_free_fs_root(ext2_root->fs_info, ext2_root);
ret = close_ctree(root);
if (ret) {
fprintf(stderr, "error during close_ctree %d\n", ret);
goto fail;
}
close_ext2fs(ext2_fs);
/*
* If this step succeed, we get a mountable btrfs. Otherwise
* the ext2fs is left unchanged.
*/
ret = migrate_super_block(fd, super_bytenr, blocksize);
if (ret) {
fprintf(stderr, "unable to migrate super block\n");
goto fail;
}
root = open_ctree_fd(fd, devname, 0, O_RDWR);
if (!root) {
fprintf(stderr, "unable to open ctree\n");
goto fail;
}
/* move chunk tree into system chunk. */
ret = fixup_chunk_mapping(root);
if (ret) {
fprintf(stderr, "error during fixup_chunk_tree\n");
goto fail;
}
ret = close_ctree(root);
close(fd);
printf("conversion complete.\n");
return 0;
fail:
fprintf(stderr, "conversion aborted.\n");
return -1;
}
static int may_rollback(struct btrfs_root *root)
{
struct btrfs_fs_info *info = root->fs_info;
struct btrfs_multi_bio *multi = NULL;
u64 bytenr;
u64 length;
u64 physical;
u64 total_bytes;
int num_stripes;
int ret;
if (btrfs_super_num_devices(&info->super_copy) != 1)
goto fail;
bytenr = BTRFS_SUPER_INFO_OFFSET;
total_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
while (1) {
ret = btrfs_map_block(&info->mapping_tree, WRITE, bytenr,
&length, &multi, 0);
if (ret)
goto fail;
num_stripes = multi->num_stripes;
physical = multi->stripes[0].physical;
kfree(multi);
if (num_stripes != 1 || physical != bytenr)
goto fail;
bytenr += length;
if (bytenr >= total_bytes)
break;
}
return 0;
fail:
return -1;
}
int do_rollback(const char *devname, int force)
{
int fd;
int ret;
int i;
struct btrfs_root *root;
struct btrfs_root *ext2_root;
struct btrfs_root *chunk_root;
struct btrfs_dir_item *dir;
struct btrfs_inode_item *inode;
struct btrfs_file_extent_item *fi;
struct btrfs_trans_handle *trans;
struct extent_buffer *leaf;
struct btrfs_block_group_cache *cache1;
struct btrfs_block_group_cache *cache2;
struct btrfs_key key;
struct btrfs_path path;
struct extent_io_tree io_tree;
char *buf;
char *name;
u64 bytenr;
u64 num_bytes;
u64 root_dir;
u64 objectid;
u64 offset;
u64 start;
u64 end;
u64 sb_bytenr;
u64 first_free;
u64 total_bytes;
u32 sectorsize;
extent_io_tree_init(&io_tree);
fd = open(devname, O_RDWR);
if (fd < 0) {
fprintf(stderr, "unable to open %s\n", devname);
goto fail;
}
root = open_ctree_fd(fd, devname, 0, O_RDWR);
if (!root) {
fprintf(stderr, "unable to open ctree\n");
goto fail;
}
ret = may_rollback(root);
if (ret < 0) {
fprintf(stderr, "unable to do rollback\n");
goto fail;
}
sectorsize = root->sectorsize;
buf = malloc(sectorsize);
if (!buf) {
fprintf(stderr, "unable to allocate memory\n");
goto fail;
}
btrfs_init_path(&path);
key.objectid = EXT2_IMAGE_SUBVOL_OBJECTID;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = (u64)-1;
ext2_root = btrfs_read_fs_root(root->fs_info, &key);
if (!ext2_root || IS_ERR(ext2_root)) {
fprintf(stderr, "unable to open subvol %llu\n",
key.objectid);
goto fail;
}
name = "image";
root_dir = btrfs_root_dirid(&root->root_item);
dir = btrfs_lookup_dir_item(NULL, ext2_root, &path,
root_dir, name, strlen(name), 0);
if (!dir || IS_ERR(dir)) {
fprintf(stderr, "unable to find file %s\n", name);
goto fail;
}
leaf = path.nodes[0];
btrfs_dir_item_key_to_cpu(leaf, dir, &key);
btrfs_release_path(ext2_root, &path);
objectid = key.objectid;
ret = btrfs_lookup_inode(NULL, ext2_root, &path, &key, 0);
if (ret) {
fprintf(stderr, "unable to find inode item\n");
goto fail;
}
leaf = path.nodes[0];
inode = btrfs_item_ptr(leaf, path.slots[0], struct btrfs_inode_item);
total_bytes = btrfs_inode_size(leaf, inode);
btrfs_release_path(ext2_root, &path);
key.objectid = objectid;
key.offset = 0;
btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
ret = btrfs_search_slot(NULL, ext2_root, &key, &path, 0, 0);
if (ret != 0) {
fprintf(stderr, "unable to find first file extent\n");
btrfs_release_path(ext2_root, &path);
goto fail;
}
/* build mapping tree for the relocated blocks */
for (offset = 0; offset < total_bytes; ) {
leaf = path.nodes[0];
if (path.slots[0] >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(root, &path);
if (ret != 0)
break;
continue;
}
btrfs_item_key_to_cpu(leaf, &key, path.slots[0]);
if (key.objectid != objectid || key.offset != offset ||
btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
break;
fi = btrfs_item_ptr(leaf, path.slots[0],
struct btrfs_file_extent_item);
if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
break;
if (btrfs_file_extent_compression(leaf, fi) ||
btrfs_file_extent_encryption(leaf, fi) ||
btrfs_file_extent_other_encoding(leaf, fi))
break;
bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
/* skip holes and direct mapped extents */
if (bytenr == 0 || bytenr == offset)
goto next_extent;
bytenr += btrfs_file_extent_offset(leaf, fi);
num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
cache1 = btrfs_lookup_block_group(root->fs_info, offset);
cache2 = btrfs_lookup_block_group(root->fs_info,
offset + num_bytes - 1);
if (!cache1 || cache1 != cache2 ||
(!(cache1->flags & BTRFS_BLOCK_GROUP_SYSTEM) &&
!intersect_with_sb(offset, num_bytes)))
break;
set_extent_bits(&io_tree, offset, offset + num_bytes - 1,
EXTENT_LOCKED, GFP_NOFS);
set_state_private(&io_tree, offset, bytenr);
next_extent:
offset += btrfs_file_extent_num_bytes(leaf, fi);
path.slots[0]++;
}
btrfs_release_path(ext2_root, &path);
btrfs_free_fs_root(ext2_root->fs_info, ext2_root);
if (offset < total_bytes) {
fprintf(stderr, "unable to build extent mapping\n");
goto fail;
}
first_free = BTRFS_SUPER_INFO_OFFSET + 2 * sectorsize - 1;
first_free &= ~((u64)sectorsize - 1);
/* backup for extent #0 should exist */
if(!test_range_bit(&io_tree, 0, first_free - 1, EXTENT_LOCKED, 1)) {
fprintf(stderr, "no backup for the first extent\n");
goto fail;
}
/* force no allocation from system block group */
root->fs_info->system_allocs = -1;
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
/*
* recow the whole chunk tree, this will remove all chunk tree blocks
* from system block group
*/
chunk_root = root->fs_info->chunk_root;
memset(&key, 0, sizeof(key));
while (1) {
ret = btrfs_search_slot(trans, chunk_root, &key, &path, 0, 1);
if (ret < 0)
break;
ret = btrfs_next_leaf(chunk_root, &path);
if (ret)
break;
btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
btrfs_release_path(chunk_root, &path);
}
btrfs_release_path(chunk_root, &path);
offset = 0;
num_bytes = 0;
while(1) {
cache1 = btrfs_lookup_block_group(root->fs_info, offset);
if (!cache1)
break;
if (cache1->flags & BTRFS_BLOCK_GROUP_SYSTEM)
num_bytes += btrfs_block_group_used(&cache1->item);
offset = cache1->key.objectid + cache1->key.offset;
}
/* only extent #0 left in system block group? */
if (num_bytes > first_free) {
fprintf(stderr, "unable to empty system block group\n");
goto fail;
}
/* create a system chunk that maps the whole device */
ret = prepare_system_chunk_sb(&root->fs_info->super_copy);
if (ret) {
fprintf(stderr, "unable to update system chunk\n");
goto fail;
}
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
ret = close_ctree(root);
if (ret) {
fprintf(stderr, "error during close_ctree %d\n", ret);
goto fail;
}
/* zero btrfs super block mirrors */
memset(buf, 0, sectorsize);
for (i = 1 ; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
if (bytenr >= total_bytes)
break;
ret = pwrite(fd, buf, sectorsize, bytenr);
}
sb_bytenr = (u64)-1;
/* copy all relocated blocks back */
while(1) {
ret = find_first_extent_bit(&io_tree, 0, &start, &end,
EXTENT_LOCKED);
if (ret)
break;
ret = get_state_private(&io_tree, start, &bytenr);
BUG_ON(ret);
clear_extent_bits(&io_tree, start, end, EXTENT_LOCKED,
GFP_NOFS);
while (start <= end) {
if (start == BTRFS_SUPER_INFO_OFFSET) {
sb_bytenr = bytenr;
goto next_sector;
}
ret = pread(fd, buf, sectorsize, bytenr);
if (ret < 0) {
fprintf(stderr, "error during pread %d\n", ret);
goto fail;
}
BUG_ON(ret != sectorsize);
ret = pwrite(fd, buf, sectorsize, start);
if (ret < 0) {
fprintf(stderr, "error during pwrite %d\n", ret);
goto fail;
}
BUG_ON(ret != sectorsize);
next_sector:
start += sectorsize;
bytenr += sectorsize;
}
}
ret = fsync(fd);
if (ret) {
fprintf(stderr, "error during fsync %d\n", ret);
goto fail;
}
/*
* finally, overwrite btrfs super block.
*/
ret = pread(fd, buf, sectorsize, sb_bytenr);
if (ret < 0) {
fprintf(stderr, "error during pread %d\n", ret);
goto fail;
}
BUG_ON(ret != sectorsize);
ret = pwrite(fd, buf, sectorsize, BTRFS_SUPER_INFO_OFFSET);
if (ret < 0) {
fprintf(stderr, "error during pwrite %d\n", ret);
goto fail;
}
BUG_ON(ret != sectorsize);
ret = fsync(fd);
if (ret) {
fprintf(stderr, "error during fsync %d\n", ret);
goto fail;
}
close(fd);
free(buf);
extent_io_tree_cleanup(&io_tree);
printf("rollback complete.\n");
return 0;
fail:
fprintf(stderr, "rollback aborted.\n");
return -1;
}
static void print_usage(void)
{
printf("usage: btrfs-convert [-d] [-i] [-n] [-r] device\n");
printf("\t-d disable data checksum\n");
printf("\t-i ignore xattrs and ACLs\n");
printf("\t-n disable packing of small files\n");
printf("\t-r roll back to ext2fs\n");
}
int main(int argc, char *argv[])
{
int ret;
int packing = 1;
int noxattr = 0;
int datacsum = 1;
int rollback = 0;
char *file;
while(1) {
int c = getopt(argc, argv, "dinr");
if (c < 0)
break;
switch(c) {
case 'd':
datacsum = 0;
break;
case 'i':
noxattr = 1;
break;
case 'n':
packing = 0;
break;
case 'r':
rollback = 1;
break;
default:
print_usage();
return 1;
}
}
argc = argc - optind;
if (argc != 1) {
print_usage();
return 1;
}
file = argv[optind];
if (check_mounted(file)) {
fprintf(stderr, "%s is mounted\n", file);
return 1;
}
if (rollback) {
ret = do_rollback(file, 0);
} else {
ret = do_convert(file, datacsum, packing, noxattr);
}
if (ret)
return 1;
return 0;
}