Hello,
This patch adds customized find_free_extent support to btrfs-progs,
the conversion program requires this.
The attachment is the ext3 to btrfs conversion program. it can be
compiled by add following two line to btrfs-progs's Makefile.
convert: $(objects) convert.o utils.o
gcc $(CFLAGS) -o convert $(objects) convert.o utils.o -luuid -lext2fs
$(LDFLAGS)
Regards
YZ
----
diff -ur a/ctree.h b/ctree.h
--- a/ctree.h 2008-01-04 13:36:25.000000000 +0800
+++ b/ctree.h 2008-01-04 13:28:44.000000000 +0800
@@ -299,6 +299,13 @@
u64 pinned;
};
+struct btrfs_extent_ops {
+ int (*alloc_extent)(struct btrfs_root *root, u64 num_bytes,
+ u64 hint_byte, struct btrfs_key *ins);
+ int (*free_extent)(struct btrfs_root *root, u64 bytenr,
+ u64 num_bytes);
+};
+
struct btrfs_fs_info {
u8 fsid[BTRFS_FSID_SIZE];
struct btrfs_root *fs_root;
@@ -322,6 +329,9 @@
struct mutex fs_mutex;
int fp;
u64 total_pinned;
+
+ struct btrfs_extent_ops *extent_ops;
+ void *priv_data;
};
/*
diff -ur a/disk-io.c b/disk-io.c
--- a/disk-io.c 2008-01-04 14:43:44.000000000 +0800
+++ b/disk-io.c 2008-01-04 13:29:09.000000000 +0800
@@ -396,6 +397,8 @@
fs_info->fs_root = root;
fs_info->tree_root = tree_root;
fs_info->extent_root = extent_root;
+ fs_info->extent_ops = NULL;
+ fs_info->priv_data = NULL;
extent_map_tree_init(&fs_info->extent_cache);
extent_map_tree_init(&fs_info->free_space_cache);
diff -ur a/extent-tree.c b/extent-tree.c
--- a/extent-tree.c 2008-01-04 13:14:16.000000000 +0800
+++ b/extent-tree.c 2008-01-04 13:08:39.000000000 +0800
@@ -1209,6 +1209,7 @@
struct btrfs_path *path;
struct btrfs_key key;
struct btrfs_fs_info *info = root->fs_info;
+ struct btrfs_extent_ops *ops = info->extent_ops;
struct btrfs_root *extent_root = info->extent_root;
struct extent_buffer *leaf;
int ret;
@@ -1274,9 +1275,12 @@
root_used - num_bytes);
ret = btrfs_del_item(trans, extent_root, path);
- if (ret) {
+ if (ret)
return ret;
- }
+
+ if (ops && ops->free_extent)
+ ops->free_extent(root, bytenr, num_bytes);
+
ret = update_block_group(trans, root, bytenr, num_bytes, 0,
mark_free, 0);
BUG_ON(ret);
@@ -1626,6 +1630,7 @@
u64 new_hint;
*/
struct btrfs_fs_info *info = root->fs_info;
+ struct btrfs_extent_ops *ops = info->extent_ops;
struct btrfs_root *extent_root = info->extent_root;
struct btrfs_extent_item extent_item;
struct btrfs_path *path;
@@ -1639,10 +1644,14 @@
*/
WARN_ON(num_bytes < root->sectorsize);
- ret = find_free_extent(trans, root, num_bytes, empty_size,
- search_start, search_end, hint_byte, ins,
- trans->alloc_exclude_start,
- trans->alloc_exclude_nr, data);
+ if (ops && ops->alloc_extent) {
+ ret = ops->alloc_extent(root, num_bytes, hint_byte, ins);
+ } else {
+ ret = find_free_extent(trans, root, num_bytes, empty_size,
+ search_start, search_end, hint_byte,
+ ins, trans->alloc_exclude_start,
+ trans->alloc_exclude_nr, data);
+ }
BUG_ON(ret);
if (ret)
return ret;
/*
* 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 <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 "utils.h"
#include "ext2fs/ext2_fs.h"
#include "ext2fs/ext2fs.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(char *name, ext2_filsys *ret_fs)
{
int mnt_flags;
errcode_t ret;
ext2_filsys ext2_fs;
ret = ext2fs_check_if_mounted(name, &mnt_flags);
if (ret) {
fprintf(stderr, "ext2fs_check_if_mounted: %s\n",
error_message(ret));
return -1;
}
if (mnt_flags & EXT2_MF_MOUNTED) {
fprintf(stderr, "%s is mounted\n", name);
return -1;
}
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;
}
/*
* Stupid algorithm, search forward starting from the first free block.
*/
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 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)
return ret;
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;
}
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;
u32 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 single file extent. do all required works:
* 1. insert a btrfs_file_extent_item into fs tree.
* 2. compute checksum and insert btrfs_csum_item into fs tree.
* 3. insert extent item and extent backref into extent tree.
*/
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,
struct ext2_inode *ext2_inode)
{
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 = 1,
.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 (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, 1);
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, 1);
}
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, ext2_inode);
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;
}
#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, 0);
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 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);
ret = 0;
switch (ext2_inode.i_mode & S_IFMT) {
case S_IFREG:
ret = create_file_extents(trans, root, objectid, &btrfs_inode,
ext2_fs, ext2_ino, &ext2_inode);
break;
case S_IFLNK:
ret = create_symbol_link(trans, root, objectid, &btrfs_inode,
ext2_fs, ext2_ino, &ext2_inode);
break;
case S_IFDIR:
ret = create_dir_entries(trans, root, objectid,
&btrfs_inode, ext2_fs, ext2_ino);
break;
default:
ret = 0;
break;
}
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 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);
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_ref(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.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = num_bytes;
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.
*/
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 = 1,
.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_ref(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, 1);
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, 1);
if (ret)
return ret;
}
fail:
return 0;
}
/*
* Create the ext2fs image file.
*/
static int create_ext2_image(struct btrfs_root *root, char *name,
int namelen, ext2_filsys ext2_fs)
{
int ret;
struct btrfs_key key;
struct btrfs_key location;
struct btrfs_path path;
struct btrfs_inode_item btrfs_inode;
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 | 0444);
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, 1);
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);
btrfs_release_path(extent_root, &path);
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;
}
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, 1);
if (ret)
goto fail;
last_byte = bytenr + num_bytes;
goto again;
}
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, namelen,
btrfs_root_dirid(&root->root_item),
&location, EXT2_FT_REG_FILE);
if (ret)
goto fail;
ret = btrfs_insert_inode_ref(trans, root, name, namelen, objectid,
btrfs_root_dirid(&root->root_item));
if (ret)
goto fail;
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,
char *name, int namelen)
{
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, namelen,
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, namelen, 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) {
return NULL;
}
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.
* This function is dangerous, it modifies a block used by ext2fs.
*/
static int migrate_super_block(struct btrfs_root *root, u64 sb_offset)
{
int ret = -1;
struct extent_buffer *old_eb;
struct extent_buffer *sb_buffer;
struct btrfs_trans_handle *trans;
BUG_ON(sb_offset != BTRFS_SUPER_INFO_OFFSET);
sb_buffer = read_tree_block(root, sb_offset, 512);
if (!sb_buffer)
goto fail;
memset_extent_buffer(sb_buffer, 0, 0, sb_buffer->len);
old_eb = root->fs_info->sb_buffer;
root->fs_info->sb_buffer = sb_buffer;
btrfs_set_super_bytenr(&root->fs_info->super_copy, sb_offset);
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
ret = btrfs_free_extent(trans, root, old_eb->start, root->leafsize,
0, 0, 0, 0, 1);
if (ret)
goto fail;
ret = btrfs_commit_transaction(trans, root);
free_extent_buffer(old_eb);
BUG_ON(ret);
fail:
return ret;
}
int main(int argc, char *argv[])
{
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 *snap_root;
if (argc != 2) {
fprintf(stderr, "usage: %s device\n", argv[0]);
exit(1);
}
ret = open_ext2fs(argv[1], &ext2_fs);
if (ret) {
fprintf(stderr, "failed 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, "missing filetype feature\n");
goto fail;
}
for (i = 0; i < 4; i++) {
ret = ext2_alloc_block(ext2_fs, 0, blocks + i);
if (ret) {
fprintf(stderr, "free space isn't enough\n");
goto fail;
}
blocks[i] *= blocksize;
}
super_bytenr = blocks[0];
fd = open(argv[1], O_RDWR);
if (fd < 0) {
fprintf(stderr, "unable to open %s\n", argv[1]);
goto fail;
}
ret = make_btrfs(fd, blocks, total_bytes, blocksize,
blocksize, blocksize, blocksize);
if (ret) {
fprintf(stderr, "failed to create ctree\n");
goto fail;
}
root = open_ctree_fd(fd, super_bytenr);
if (!root) {
fprintf(stderr, "failed to open ctree\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, "failed to setup the root tree\n");
goto fail;
}
snap_root = create_subvol(root, "ext2_saved", 10);
if (!snap_root) {
fprintf(stderr, "failed to create subvol\n");
goto fail;
}
printf("creating btrfs metadata.\n");
ret = copy_inodes(root, ext2_fs);
if (ret) {
fprintf(stderr, "error during copy_inodes %d\n", ret);
goto fail;
}
printf("creating ext2fs image file.\n");
ret = create_ext2_image(snap_root, "image", 5, ext2_fs);
if (ret) {
fprintf(stderr, "failed to create fs image\n");
goto fail;
}
ret = migrate_super_block(root, BTRFS_SUPER_INFO_OFFSET);
if (ret) {
fprintf(stderr, "failed to update super block\n");
goto fail;
}
btrfs_free_fs_root(snap_root->fs_info, snap_root);
ret = close_ctree(root);
if (ret) {
fprintf(stderr, "error during close_ctree %d\n", ret);
goto fail;
}
close_ext2fs(ext2_fs);
printf("conversion complete.\n");
exit(0);
fail:
fprintf(stderr, "conversion abort.\n");
exit(1);
}
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