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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 500
#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 "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)
/*
* 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;
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;
}
*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 custom_alloc_extent(struct btrfs_root *root, u64 num_bytes,
u64 hint_byte, struct btrfs_key *ins)
{
ext2_filsys fs = (ext2_filsys)root->fs_info->priv_data;
u32 blocksize = fs->blocksize;
u64 first = 0;
u64 block;
u64 bytenr;
int ret;
block = hint_byte / blocksize;
BUG_ON(block != (blk_t)block);
BUG_ON(num_bytes != blocksize);
while (1) {
ret = ext2_alloc_block(fs, block, &block);
if (ret)
goto fail;
/* all free blocks are pinned */
if (first == block)
goto fail;
if (first == 0)
first = block;
bytenr = block * blocksize;
if (!test_range_bit(&root->fs_info->pinned_extents, bytenr,
bytenr + blocksize - 1, EXTENT_DIRTY, 0))
break;
ext2_free_block(fs, block);
block++;
}
ins->objectid = bytenr;
ins->offset = blocksize;
btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
return 0;
fail:
fprintf(stderr, "not enough free space\n");
return -ENOSPC;
}
static int custom_free_extent(struct btrfs_root *root, u64 bytenr,
u64 num_bytes)
{
u64 block;
ext2_filsys fs = (ext2_filsys)root->fs_info->priv_data;
BUG_ON(bytenr & (fs->blocksize - 1));
block = bytenr / fs->blocksize;
while (num_bytes > 0) {
ext2_free_block(fs, block);
block++;
num_bytes -= fs->blocksize;
}
return 0;
}
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 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]);
if (ret)
goto fail;
ret = btrfs_insert_inode_ref(idata->trans, idata->root,
dirent->name, dirent->name_len,
objectid, idata->objectid);
if (ret)
goto fail;
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,
.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);
}
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_info *fs_info = root->fs_info;
ret = pread(fs_info->fp, 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 btrfs_key ins_key;
struct btrfs_path path;
struct btrfs_extent_item extent_item;
u32 blocksize = root->sectorsize;
u64 nblocks;
u64 bytes_used;
ret = btrfs_insert_file_extent(trans, root, objectid, file_pos,
disk_bytenr, num_bytes, num_bytes);
if (ret || disk_bytenr == 0)
return ret;
nblocks = btrfs_stack_inode_nblocks(inode) + num_bytes / 512;
btrfs_set_stack_inode_nblocks(inode, nblocks);
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, inode,
objectid, file_pos + offset,
buffer, blocksize);
if (ret)
break;
}
free(buffer);
if (ret)
goto fail;
}
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, 1);
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);
btrfs_init_path(&path);
ret = btrfs_insert_extent_backref(trans, extent_root, &path,
disk_bytenr, root->root_key.objectid,
trans->transid, objectid, file_pos);
if (ret)
goto fail;
ret = btrfs_update_block_group(trans, root, disk_bytenr,
num_bytes, 1, 0, 1);
} else if (ret == -EEXIST) {
ret = btrfs_inc_extent_ref(trans, root, disk_bytenr, num_bytes,
root->root_key.objectid,
trans->transid, objectid, file_pos);
}
if (ret)
goto fail;
btrfs_extent_post_op(trans, extent_root);
return 0;
fail:
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;
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;
u32 blocksize = ext2_fs->blocksize;
struct btrfs_root *root = idata->root;
struct btrfs_trans_handle *trans = idata->trans;
if ((file_block > idata->first_block + idata->num_blocks) ||
(disk_block != idata->disk_block + idata->num_blocks) ||
(idata->num_blocks >= BTRFS_BLOCK_GROUP_SIZE / blocksize)) {
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;
}
idata->first_block = file_block;
idata->disk_block = disk_block;
}
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,
.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;
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;
} 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);
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)
{
btrfs_set_stack_inode_generation(dst, 1);
btrfs_set_stack_inode_size(dst, src->i_size);
btrfs_set_stack_inode_nblocks(dst, src->i_blocks);
btrfs_set_stack_inode_block_group(dst, 0);
btrfs_set_stack_inode_nblocks(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_inode_compat_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) && !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,
int datacsum, int packing, int noxattr)
{
int ret;
errcode_t err;
struct ext2_inode ext2_inode;
struct btrfs_key inode_key;
struct btrfs_inode_item btrfs_inode;
err = ext2fs_read_inode(ext2_fs, ext2_ino, &ext2_inode);
if (err)
goto error;
if (!ext2_inode.i_links_count &&
(!ext2_inode.i_mode || ext2_inode.i_dtime)) {
printf("skip inode %u\n", ext2_ino);
return 0;
}
copy_inode_item(&btrfs_inode, &ext2_inode);
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;
error:
fprintf(stderr, "ext2fs_read_inode: %s\n", error_message(err));
return -1;
}
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_info *fs_info = root->fs_info;
buffer = malloc(num_bytes);
if (!buffer)
return -ENOMEM;
ret = pread(fs_info->fp, buffer, num_bytes, src_bytenr);
if (ret != num_bytes)
goto fail;
ret = pwrite(fs_info->fp, 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;
ext2_ino_t ext2_ino;
u64 objectid;
struct btrfs_trans_handle *trans;
trans = btrfs_start_transaction(root, 1);
if (!trans)
return -ENOMEM;
ext2_ino = ext2_fs->inode_map->start;
for (; ext2_ino <= ext2_fs->inode_map->end; ext2_ino++) {
if (ext2fs_fast_test_inode_bitmap(ext2_fs->inode_map,
ext2_ino)) {
/* 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,
datacsum, packing, noxattr);
if (ret)
return ret;
}
if (trans->blocks_used >= 8192) {
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
}
}
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
return ret;
}
static int lookup_extent_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, u64 num_bytes)
{
int ret;
struct btrfs_key key;
struct btrfs_path path;
btrfs_init_path(&path);
key.objectid = bytenr;
key.offset = num_bytes;
btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
ret = btrfs_search_slot(trans, root->fs_info->extent_root,
&key, &path, 0, 0);
btrfs_release_path(root, &path);
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)
{
u64 bytenr;
u32 blocksize = ext2_fs->blocksize;
u32 block = start_byte / blocksize;
u32 last_block = (end_byte + blocksize - 1) / blocksize;
int ret;
struct blk_iterate_data data = {
.trans = trans,
.root = root,
.inode = inode,
.objectid = objectid,
.first_block = block,
.disk_block = block,
.num_blocks = 0,
.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;
/* the bit may be set by us, check extent tree */
bytenr = (u64)block * blocksize;
ret = lookup_extent_item(trans, root, bytenr, blocksize);
if (ret < 0)
goto fail;
if (ret == 0)
continue;
ret = block_iterate_proc(ext2_fs, block, block, &data);
if (ret & BLOCK_ABORT)
break;
}
ret = data.errcode;
if (ret)
return ret;
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)
return ret;
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)
return ret;
}
fail:
return 0;
}
/*
* 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 new_block;
u64 last_byte;
u64 first_free;
u64 total_bytes;
u32 sectorsize = root->sectorsize;
int slot;
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_nblocks(&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 the first a few blocks to new positions. the relocation is
* reuqired for block 0 and default btrfs super block.
*/
for (last_byte = 0; last_byte < first_free; last_byte += sectorsize) {
ret = ext2_alloc_block(ext2_fs, 0, &new_block);
if (ret)
goto fail;
new_block *= sectorsize;
ret = copy_disk_extent(root, new_block, last_byte, sectorsize);
if (ret)
goto fail;
ret = record_file_extent(trans, root, objectid,
&btrfs_inode, last_byte,
new_block, sectorsize, 0);
if (ret)
goto fail;
}
again:
if (trans->blocks_used >= 8192) {
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
}
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;
leaf = path.nodes[0];
slot = path.slots[0];
while(1) {
if (slot >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(extent_root, &path);
if (ret < 0)
goto fail;
if (ret > 0)
break;
leaf = path.nodes[0];
slot = path.slots[0];
}
btrfs_item_key_to_cpu(leaf, &key, slot);
if (last_byte > key.objectid ||
key.type != BTRFS_EXTENT_ITEM_KEY) {
slot++;
continue;
}
/*
* 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 (slot >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(extent_root, &path);
if (ret > 0)
break;
if (ret < 0)
goto fail;
leaf = path.nodes[0];
slot = path.slots[0];
}
btrfs_item_key_to_cpu(leaf, &key, slot);
if (key.objectid != bytenr)
break;
if (key.type != BTRFS_EXTENT_REF_KEY) {
slot++;
continue;
}
ref_item = btrfs_item_ptr(leaf, slot,
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;
}
slot++;
}
if (!file_extent)
continue;
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(root, &path);
goto again;
}
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;
}
/*
* otime isn't used currently, so we can store some data in it.
* These data are used by do_rollback to check whether the image
* file has been modified.
*/
btrfs_set_stack_timespec_sec(&btrfs_inode.otime, trans->transid);
btrfs_set_stack_timespec_nsec(&btrfs_inode.otime,
total_bytes / sectorsize);
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);
if (ret)
goto fail;
ret = btrfs_insert_inode_ref(trans, root, name, strlen(name),
objectid,
btrfs_root_dirid(&root->root_item));
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 *create_subvol(struct btrfs_root *root, const char *name)
{
int ret;
u64 objectid;
struct btrfs_key location;
struct btrfs_root_item root_item;
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;
struct extent_buffer *tmp;
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
objectid = btrfs_super_root_dir(&fs_info->super_copy);
ret = btrfs_find_free_objectid(trans, root, objectid, &objectid);
if (ret)
goto fail;
ret = btrfs_copy_root(trans, root, root->node, &tmp, objectid);
if (ret)
goto fail;
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));
free_extent_buffer(tmp);
location.objectid = objectid;
location.offset = 1;
btrfs_set_key_type(&location, BTRFS_ROOT_ITEM_KEY);
ret = btrfs_insert_root(trans, root->fs_info->tree_root,
&location, &root_item);
if (ret)
goto fail;
location.offset = (u64)-1;
ret = btrfs_insert_dir_item(trans, tree_root, name, strlen(name),
btrfs_super_root_dir(&fs_info->super_copy),
&location, BTRFS_FT_DIR);
if (ret)
goto fail;
ret = btrfs_insert_inode_ref(trans, tree_root, name, strlen(name),
objectid,
btrfs_super_root_dir(&fs_info->super_copy));
if (ret)
goto fail;
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
new_root = btrfs_read_fs_root(fs_info, &location);
if (!new_root || IS_ERR(new_root))
goto fail;
trans = btrfs_start_transaction(new_root, 1);
BUG_ON(!trans);
ret = btrfs_make_root_dir(trans, new_root, BTRFS_FIRST_FREE_OBJECTID);
if (ret)
goto fail;
ret = btrfs_commit_transaction(trans, new_root);
BUG_ON(ret);
return new_root;
fail:
return NULL;
}
/*
* 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);
}
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, 1);
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 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 = 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);
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));
if (ret)
goto err;
btrfs_set_root_dirid(&fs_info->fs_root->root_item,
BTRFS_FIRST_FREE_OBJECTID);
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;
char *buf;
u64 bytenr;
u32 crc = ~(u32)0;
u32 len = 512 - BTRFS_CSUM_SIZE;
struct btrfs_super_block *super;
ret = fsync(fd);
if (ret)
goto fail;
BUG_ON(sectorsize < sizeof(super));
buf = malloc(sectorsize);
if (!buf)
return -ENOMEM;
ret = pread(fd, buf, sectorsize, old_bytenr);
if (ret != sectorsize)
goto fail;
super = (struct btrfs_super_block *)buf;
BUG_ON(btrfs_super_bytenr(super) != old_bytenr);
btrfs_set_super_bytenr(super, BTRFS_SUPER_INFO_OFFSET);
crc = crc32c(crc, buf + BTRFS_CSUM_SIZE, len);
crc = ~cpu_to_le32(crc);
memcpy(super->csum, &crc, BTRFS_CRC32_SIZE);
ret = pwrite(fd, buf, sectorsize, BTRFS_SUPER_INFO_OFFSET);
if (ret < 0)
goto fail;
/* How to handle this case? */
BUG_ON(ret != sectorsize);
ret = fsync(fd);
if (ret)
goto fail;
memset(buf, 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, 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;
}
int do_convert(const char *devname, int datacsum, int packing, int noxattr)
{
int i, fd, ret;
u32 blocksize;
u64 blocks[4];
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;
}
for (i = 0; i < 4; 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, blocks, total_bytes, blocksize,
blocksize, blocksize, blocksize);
if (ret) {
fprintf(stderr, "unable to create initial ctree\n");
goto fail;
}
root = open_ctree_fd(fd, super_bytenr);
if (!root) {
fprintf(stderr, "unable to open ctree\n");
goto fail;
}
fd = dup(fd);
if (fd < 0) {
fprintf(stderr, "unable to duplicate file descriptor\n");
goto fail;
}
root->fs_info->priv_data = ext2_fs;
root->fs_info->extent_ops = &extent_ops;
ret = init_btrfs(root);
if (ret) {
fprintf(stderr, "unable to setup the root tree\n");
goto fail;
}
ext2_root = create_subvol(root, "ext2_saved");
if (!ext2_root) {
fprintf(stderr, "unable to create subvol\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");
ret = create_ext2_image(ext2_root, ext2_fs, "image");
if (ret) {
fprintf(stderr, "error during create_ext2_image %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);
/* finally migrate super block to its default postion */
ret = migrate_super_block(fd, super_bytenr, blocksize);
if (ret) {
fprintf(stderr, "unable to migrate super block\n");
goto fail;
}
close(fd);
printf("conversion complete.\n");
return 0;
fail:
fprintf(stderr, "conversion aborted.\n");
return -1;
}
int do_rollback(const char *devname, int force)
{
int fd;
int ret;
int modified = 0;
struct btrfs_root *root;
struct btrfs_root *ext2_root;
struct btrfs_dir_item *dir;
struct btrfs_inode_item *inode;
struct btrfs_file_extent_item *fi;
struct btrfs_inode_timespec *tspec;
struct extent_buffer *leaf;
struct btrfs_key key;
struct btrfs_path path;
char *buf;
char *name;
u64 bytenr;
u64 num_bytes;
u64 root_dir;
u64 objectid;
u64 offset;
u64 first_free;
u64 last_trans;
u64 total_bytes;
fd = open(devname, O_RDWR);
if (fd < 0) {
fprintf(stderr, "unable to open %s\n", devname);
goto fail;
}
root = open_ctree_fd(fd, 0);
if (!root) {
fprintf(stderr, "unable to open ctree\n");
goto fail;
}
fd = dup(fd);
if (fd < 0) {
fprintf(stderr, "unable to duplicate file descriptor\n");
goto fail;
}
first_free = BTRFS_SUPER_INFO_OFFSET + root->sectorsize * 2 - 1;
first_free &= ~((u64)root->sectorsize - 1);
buf = malloc(first_free);
if (!buf) {
fprintf(stderr, "unable to allocate memory\n");
goto fail;
}
btrfs_init_path(&path);
name = "ext2_saved";
root_dir = btrfs_super_root_dir(&root->fs_info->super_copy);
dir = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, &path,
root_dir, name, strlen(name), 0);
if (!dir || IS_ERR(dir)) {
fprintf(stderr, "unable to find subvol %s\n", name);
goto fail;
}
leaf = path.nodes[0];
btrfs_dir_item_key_to_cpu(leaf, dir, &key);
btrfs_release_path(root->fs_info->tree_root, &path);
ext2_root = btrfs_read_fs_root(root->fs_info, &key);
if (!ext2_root || IS_ERR(ext2_root)) {
fprintf(stderr, "unable to open subvol %s\n", name);
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);
tspec = btrfs_inode_otime(inode);
/*
* get image file size and transaction id stored in 'otime' field.
* see comments in create_ext2_image.
*/
last_trans = btrfs_timespec_sec(leaf, tspec);
total_bytes = btrfs_timespec_nsec(leaf, tspec);
total_bytes *= root->sectorsize;
btrfs_release_path(ext2_root, &path);
if (total_bytes < first_free ||
total_bytes != btrfs_inode_size(leaf, inode)) {
fprintf(stderr, "image file size mismatch\n");
goto fail;
}
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;
}
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_generation(leaf, fi) > last_trans) {
modified = 1;
break;
}
if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
break;
if (offset >= first_free)
goto next;
bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
if (bytenr == 0)
break;
bytenr += btrfs_file_extent_offset(leaf, fi);
num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
if (num_bytes > first_free - offset)
num_bytes = first_free - offset;
ret = pread(fd, buf + offset, num_bytes, bytenr);
if (ret != num_bytes) {
fprintf(stderr, "unable to read required data\n");
btrfs_release_path(ext2_root, &path);
goto fail;
}
next:
offset += btrfs_file_extent_num_bytes(leaf, fi);
path.slots[0]++;
}
btrfs_release_path(ext2_root, &path);
if (modified) {
fprintf(stderr, "image file has been modified\n");
goto fail;
}
if (offset < total_bytes) {
fprintf(stderr, "unable to check all file extents\n");
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;
}
ret = pwrite(fd, buf, first_free, 0);
if (ret < 0) {
fprintf(stderr, "error during pwrite %d\n", ret);
goto fail;
}
/* How to handle this case? */
BUG_ON(ret != first_free);
ret = fsync(fd);
if (ret) {
fprintf(stderr, "error during fsync %d\n", ret);
goto fail;
}
close(fd);
free(buf);
printf("rollback complete.\n");
return 0;
fail:
fprintf(stderr, "rollback aborted.\n");
return -1;
}
static void check_mounted(const char *name)
{
int mnt_flags;
errcode_t ret;
ret = ext2fs_check_if_mounted(name, &mnt_flags);
if (ret) {
fprintf(stderr, "ext2fs_check_if_mounted: %s\n",
error_message(ret));
exit(1);
}
if (mnt_flags & EXT2_MF_MOUNTED) {
fprintf(stderr, "%s is mounted\n", name);
exit(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");
exit(1);
}
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();
}
}
argc = argc - optind;
if (argc == 1) {
file = argv[optind];
check_mounted(file);
} else {
print_usage();
}
if (rollback) {
ret = do_rollback(file, 0);
} else {
ret = do_convert(file, datacsum, packing, noxattr);
}
if (ret)
return 1;
return 0;
}
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