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btrfs-progs/convert/main.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.
*/
#include "kerncompat.h"
#include <sys/ioctl.h>
#include <sys/mount.h>
#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/limits.h>
#include <getopt.h>
#include "ctree.h"
#include "disk-io.h"
#include "volumes.h"
#include "transaction.h"
#include "crc32c.h"
#include "utils.h"
#include "task-utils.h"
#if BTRFSCONVERT_EXT2
#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)
/*
* Compatibility code for e2fsprogs 1.41 which doesn't support RO compat flag
* BIGALLOC.
* Unlike normal RO compat flag, BIGALLOC affects how e2fsprogs check used
* space, and btrfs-convert heavily relies on it.
*/
#ifdef HAVE_OLD_E2FSPROGS
#define EXT2FS_CLUSTER_RATIO(fs) (1)
#define EXT2_CLUSTERS_PER_GROUP(s) (EXT2_BLOCKS_PER_GROUP(s))
#define EXT2FS_B2C(fs, blk) (blk)
#endif
#endif
#define CONV_IMAGE_SUBVOL_OBJECTID BTRFS_FIRST_FREE_OBJECTID
struct task_ctx {
uint32_t max_copy_inodes;
uint32_t cur_copy_inodes;
struct task_info *info;
};
static void *print_copied_inodes(void *p)
{
struct task_ctx *priv = p;
const char work_indicator[] = { '.', 'o', 'O', 'o' };
uint32_t count = 0;
task_period_start(priv->info, 1000 /* 1s */);
while (1) {
count++;
printf("copy inodes [%c] [%10d/%10d]\r",
work_indicator[count % 4], priv->cur_copy_inodes,
priv->max_copy_inodes);
fflush(stdout);
task_period_wait(priv->info);
}
return NULL;
}
static int after_copied_inodes(void *p)
{
printf("\n");
fflush(stdout);
return 0;
}
struct btrfs_convert_context;
struct btrfs_convert_operations {
const char *name;
int (*open_fs)(struct btrfs_convert_context *cctx, const char *devname);
int (*read_used_space)(struct btrfs_convert_context *cctx);
int (*copy_inodes)(struct btrfs_convert_context *cctx,
struct btrfs_root *root, int datacsum,
int packing, int noxattr, struct task_ctx *p);
void (*close_fs)(struct btrfs_convert_context *cctx);
int (*check_state)(struct btrfs_convert_context *cctx);
};
static void init_convert_context(struct btrfs_convert_context *cctx)
{
cache_tree_init(&cctx->used);
cache_tree_init(&cctx->data_chunks);
cache_tree_init(&cctx->free);
}
static void clean_convert_context(struct btrfs_convert_context *cctx)
{
free_extent_cache_tree(&cctx->used);
free_extent_cache_tree(&cctx->data_chunks);
free_extent_cache_tree(&cctx->free);
}
static inline int copy_inodes(struct btrfs_convert_context *cctx,
struct btrfs_root *root, int datacsum,
int packing, int noxattr, struct task_ctx *p)
{
return cctx->convert_ops->copy_inodes(cctx, root, datacsum, packing,
noxattr, p);
}
static inline void convert_close_fs(struct btrfs_convert_context *cctx)
{
cctx->convert_ops->close_fs(cctx);
}
static inline int convert_check_state(struct btrfs_convert_context *cctx)
{
return cctx->convert_ops->check_state(cctx);
}
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)BTRFS_STRIPE_LEN - 1);
if (bytenr < offset + BTRFS_STRIPE_LEN &&
bytenr + num_bytes > offset)
return 1;
}
return 0;
}
static int convert_insert_dirent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
const char *name, size_t name_len,
u64 dir, u64 objectid,
u8 file_type, u64 index_cnt,
struct btrfs_inode_item *inode)
{
int ret;
u64 inode_size;
struct btrfs_key location = {
.objectid = objectid,
.offset = 0,
.type = BTRFS_INODE_ITEM_KEY,
};
ret = btrfs_insert_dir_item(trans, root, name, name_len,
dir, &location, file_type, index_cnt);
if (ret)
return ret;
ret = btrfs_insert_inode_ref(trans, root, name, name_len,
objectid, dir, index_cnt);
if (ret)
return ret;
inode_size = btrfs_stack_inode_size(inode) + name_len * 2;
btrfs_set_stack_inode_size(inode, inode_size);
return 0;
}
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;
}
static int csum_disk_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 disk_bytenr, u64 num_bytes)
{
u32 blocksize = root->sectorsize;
u64 offset;
char *buffer;
int ret = 0;
buffer = malloc(blocksize);
if (!buffer)
return -ENOMEM;
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);
return ret;
}
struct blk_iterate_data {
struct btrfs_trans_handle *trans;
struct btrfs_root *root;
struct btrfs_root *convert_root;
struct btrfs_inode_item *inode;
u64 convert_ino;
u64 objectid;
u64 first_block;
u64 disk_block;
u64 num_blocks;
u64 boundary;
int checksum;
int errcode;
};
static void init_blk_iterate_data(struct blk_iterate_data *data,
struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_inode_item *inode,
u64 objectid, int checksum)
{
struct btrfs_key key;
data->trans = trans;
data->root = root;
data->inode = inode;
data->objectid = objectid;
data->first_block = 0;
data->disk_block = 0;
data->num_blocks = 0;
data->boundary = (u64)-1;
data->checksum = checksum;
data->errcode = 0;
key.objectid = CONV_IMAGE_SUBVOL_OBJECTID;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = (u64)-1;
data->convert_root = btrfs_read_fs_root(root->fs_info, &key);
/* Impossible as we just opened it before */
BUG_ON(!data->convert_root || IS_ERR(data->convert_root));
data->convert_ino = BTRFS_FIRST_FREE_OBJECTID + 1;
}
/*
* Record a file extent in original filesystem into btrfs one.
* The special point is, old disk_block can point to a reserved range.
* So here, we don't use disk_block directly but search convert_root
* to get the real disk_bytenr.
*/
static int record_file_blocks(struct blk_iterate_data *data,
u64 file_block, u64 disk_block, u64 num_blocks)
{
int ret = 0;
struct btrfs_root *root = data->root;
struct btrfs_root *convert_root = data->convert_root;
struct btrfs_path path;
u64 file_pos = file_block * root->sectorsize;
u64 old_disk_bytenr = disk_block * root->sectorsize;
u64 num_bytes = num_blocks * root->sectorsize;
u64 cur_off = old_disk_bytenr;
/* Hole, pass it to record_file_extent directly */
if (old_disk_bytenr == 0)
return btrfs_record_file_extent(data->trans, root,
data->objectid, data->inode, file_pos, 0,
num_bytes);
btrfs_init_path(&path);
/*
* Search real disk bytenr from convert root
*/
while (cur_off < old_disk_bytenr + num_bytes) {
struct btrfs_key key;
struct btrfs_file_extent_item *fi;
struct extent_buffer *node;
int slot;
u64 extent_disk_bytenr;
u64 extent_num_bytes;
u64 real_disk_bytenr;
u64 cur_len;
key.objectid = data->convert_ino;
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = cur_off;
ret = btrfs_search_slot(NULL, convert_root, &key, &path, 0, 0);
if (ret < 0)
break;
if (ret > 0) {
ret = btrfs_previous_item(convert_root, &path,
data->convert_ino,
BTRFS_EXTENT_DATA_KEY);
if (ret < 0)
break;
if (ret > 0) {
ret = -ENOENT;
break;
}
}
node = path.nodes[0];
slot = path.slots[0];
btrfs_item_key_to_cpu(node, &key, slot);
BUG_ON(key.type != BTRFS_EXTENT_DATA_KEY ||
key.objectid != data->convert_ino ||
key.offset > cur_off);
fi = btrfs_item_ptr(node, slot, struct btrfs_file_extent_item);
extent_disk_bytenr = btrfs_file_extent_disk_bytenr(node, fi);
extent_num_bytes = btrfs_file_extent_num_bytes(node, fi);
BUG_ON(cur_off - key.offset >= extent_num_bytes);
btrfs_release_path(&path);
if (extent_disk_bytenr)
real_disk_bytenr = cur_off - key.offset +
extent_disk_bytenr;
else
real_disk_bytenr = 0;
cur_len = min(key.offset + extent_num_bytes,
old_disk_bytenr + num_bytes) - cur_off;
ret = btrfs_record_file_extent(data->trans, data->root,
data->objectid, data->inode, file_pos,
real_disk_bytenr, cur_len);
if (ret < 0)
break;
cur_off += cur_len;
file_pos += cur_len;
/*
* No need to care about csum
* As every byte of old fs image is calculated for csum, no
* need to waste CPU cycles now.
*/
}
btrfs_release_path(&path);
return ret;
}
static int block_iterate_proc(u64 disk_block, u64 file_block,
struct blk_iterate_data *idata)
{
int ret = 0;
int sb_region;
int do_barrier;
struct btrfs_root *root = idata->root;
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(idata, idata->first_block,
idata->disk_block,
idata->num_blocks);
if (ret)
goto fail;
idata->first_block += idata->num_blocks;
idata->num_blocks = 0;
}
if (file_block > idata->first_block) {
ret = record_file_blocks(idata, idata->first_block,
0, file_block - idata->first_block);
if (ret)
goto fail;
}
if (sb_region) {
bytenr += BTRFS_STRIPE_LEN - 1;
bytenr &= ~((u64)BTRFS_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++;
fail:
return ret;
}
static int create_image_file_range(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct cache_tree *used,
struct btrfs_inode_item *inode,
u64 ino, u64 bytenr, u64 *ret_len,
int datacsum)
{
struct cache_extent *cache;
struct btrfs_block_group_cache *bg_cache;
u64 len = *ret_len;
u64 disk_bytenr;
int i;
int ret;
if (bytenr != round_down(bytenr, root->sectorsize)) {
error("bytenr not sectorsize aligned: %llu",
(unsigned long long)bytenr);
return -EINVAL;
}
if (len != round_down(len, root->sectorsize)) {
error("length not sectorsize aligned: %llu",
(unsigned long long)len);
return -EINVAL;
}
len = min_t(u64, len, BTRFS_MAX_EXTENT_SIZE);
/*
* Skip sb ranges first
* [0, 1M), [sb_offset(1), +64K), [sb_offset(2), +64K].
*
* Or we will insert a hole into current image file, and later
* migrate block will fail as there is already a file extent.
*/
if (bytenr < 1024 * 1024) {
*ret_len = 1024 * 1024 - bytenr;
return 0;
}
for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {
u64 cur = btrfs_sb_offset(i);
if (bytenr >= cur && bytenr < cur + BTRFS_STRIPE_LEN) {
*ret_len = cur + BTRFS_STRIPE_LEN - bytenr;
return 0;
}
}
for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {
u64 cur = btrfs_sb_offset(i);
/*
* |--reserved--|
* |----range-------|
* May still need to go through file extent inserts
*/
if (bytenr < cur && bytenr + len >= cur) {
len = min_t(u64, len, cur - bytenr);
break;
}
/*
* |--reserved--|
* |---range---|
* Drop out, no need to insert anything
*/
if (bytenr >= cur && bytenr < cur + BTRFS_STRIPE_LEN) {
*ret_len = cur + BTRFS_STRIPE_LEN - bytenr;
return 0;
}
}
cache = search_cache_extent(used, bytenr);
if (cache) {
if (cache->start <= bytenr) {
/*
* |///////Used///////|
* |<--insert--->|
* bytenr
*/
len = min_t(u64, len, cache->start + cache->size -
bytenr);
disk_bytenr = bytenr;
} else {
/*
* |//Used//|
* |<-insert-->|
* bytenr
*/
len = min(len, cache->start - bytenr);
disk_bytenr = 0;
datacsum = 0;
}
} else {
/*
* |//Used//| |EOF
* |<-insert-->|
* bytenr
*/
disk_bytenr = 0;
datacsum = 0;
}
if (disk_bytenr) {
/* Check if the range is in a data block group */
bg_cache = btrfs_lookup_block_group(root->fs_info, bytenr);
if (!bg_cache)
return -ENOENT;
if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_DATA))
return -EINVAL;
/* The extent should never cross block group boundary */
len = min_t(u64, len, bg_cache->key.objectid +
bg_cache->key.offset - bytenr);
}
if (len != round_down(len, root->sectorsize)) {
error("remaining length not sectorsize aligned: %llu",
(unsigned long long)len);
return -EINVAL;
}
ret = btrfs_record_file_extent(trans, root, ino, inode, bytenr,
disk_bytenr, len);
if (ret < 0)
return ret;
if (datacsum)
ret = csum_disk_extent(trans, root, bytenr, len);
*ret_len = len;
return ret;
}
/*
* Relocate old fs data in one reserved ranges
*
* Since all old fs data in reserved range is not covered by any chunk nor
* data extent, we don't need to handle any reference but add new
* extent/reference, which makes codes more clear
*/
static int migrate_one_reserved_range(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct cache_tree *used,
struct btrfs_inode_item *inode, int fd,
u64 ino, u64 start, u64 len, int datacsum)
{
u64 cur_off = start;
u64 cur_len = len;
u64 hole_start = start;
u64 hole_len;
struct cache_extent *cache;
struct btrfs_key key;
struct extent_buffer *eb;
int ret = 0;
while (cur_off < start + len) {
cache = lookup_cache_extent(used, cur_off, cur_len);
if (!cache)
break;
cur_off = max(cache->start, cur_off);
cur_len = min(cache->start + cache->size, start + len) -
cur_off;
BUG_ON(cur_len < root->sectorsize);
/* reserve extent for the data */
ret = btrfs_reserve_extent(trans, root, cur_len, 0, 0, (u64)-1,
&key, 1);
if (ret < 0)
break;
eb = malloc(sizeof(*eb) + cur_len);
if (!eb) {
ret = -ENOMEM;
break;
}
ret = pread(fd, eb->data, cur_len, cur_off);
if (ret < cur_len) {
ret = (ret < 0 ? ret : -EIO);
free(eb);
break;
}
eb->start = key.objectid;
eb->len = key.offset;
/* Write the data */
ret = write_and_map_eb(trans, root, eb);
free(eb);
if (ret < 0)
break;
/* Now handle extent item and file extent things */
ret = btrfs_record_file_extent(trans, root, ino, inode, cur_off,
key.objectid, key.offset);
if (ret < 0)
break;
/* Finally, insert csum items */
if (datacsum)
ret = csum_disk_extent(trans, root, key.objectid,
key.offset);
/* Don't forget to insert hole */
hole_len = cur_off - hole_start;
if (hole_len) {
ret = btrfs_record_file_extent(trans, root, ino, inode,
hole_start, 0, hole_len);
if (ret < 0)
break;
}
cur_off += key.offset;
hole_start = cur_off;
cur_len = start + len - cur_off;
}
/* Last hole */
if (start + len - hole_start > 0)
ret = btrfs_record_file_extent(trans, root, ino, inode,
hole_start, 0, start + len - hole_start);
return ret;
}
/*
* Relocate the used ext2 data in reserved ranges
* [0,1M)
* [btrfs_sb_offset(1), +BTRFS_STRIPE_LEN)
* [btrfs_sb_offset(2), +BTRFS_STRIPE_LEN)
*/
static int migrate_reserved_ranges(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct cache_tree *used,
struct btrfs_inode_item *inode, int fd,
u64 ino, u64 total_bytes, int datacsum)
{
u64 cur_off;
u64 cur_len;
int ret = 0;
/* 0 ~ 1M */
cur_off = 0;
cur_len = 1024 * 1024;
ret = migrate_one_reserved_range(trans, root, used, inode, fd, ino,
cur_off, cur_len, datacsum);
if (ret < 0)
return ret;
/* second sb(fisrt sb is included in 0~1M) */
cur_off = btrfs_sb_offset(1);
cur_len = min(total_bytes, cur_off + BTRFS_STRIPE_LEN) - cur_off;
if (cur_off > total_bytes)
return ret;
ret = migrate_one_reserved_range(trans, root, used, inode, fd, ino,
cur_off, cur_len, datacsum);
if (ret < 0)
return ret;
/* Last sb */
cur_off = btrfs_sb_offset(2);
cur_len = min(total_bytes, cur_off + BTRFS_STRIPE_LEN) - cur_off;
if (cur_off > total_bytes)
return ret;
ret = migrate_one_reserved_range(trans, root, used, inode, fd, ino,
cur_off, cur_len, datacsum);
return ret;
}
/*
* Helper for expand and merge extent_cache for wipe_one_reserved_range() to
* handle wiping a range that exists in cache.
*/
static int _expand_extent_cache(struct cache_tree *tree,
struct cache_extent *entry,
u64 min_stripe_size, int backward)
{
struct cache_extent *ce;
int diff;
if (entry->size >= min_stripe_size)
return 0;
diff = min_stripe_size - entry->size;
if (backward) {
ce = prev_cache_extent(entry);
if (!ce)
goto expand_back;
if (ce->start + ce->size >= entry->start - diff) {
/* Directly merge with previous extent */
ce->size = entry->start + entry->size - ce->start;
remove_cache_extent(tree, entry);
free(entry);
return 0;
}
expand_back:
/* No overlap, normal extent */
if (entry->start < diff) {
error("cannot find space for data chunk layout");
return -ENOSPC;
}
entry->start -= diff;
entry->size += diff;
return 0;
}
ce = next_cache_extent(entry);
if (!ce)
goto expand_after;
if (entry->start + entry->size + diff >= ce->start) {
/* Directly merge with next extent */
entry->size = ce->start + ce->size - entry->start;
remove_cache_extent(tree, ce);
free(ce);
return 0;
}
expand_after:
entry->size += diff;
return 0;
}
/*
* Remove one reserve range from given cache tree
* if min_stripe_size is non-zero, it will ensure for split case,
* all its split cache extent is no smaller than @min_strip_size / 2.
*/
static int wipe_one_reserved_range(struct cache_tree *tree,
u64 start, u64 len, u64 min_stripe_size,
int ensure_size)
{
struct cache_extent *cache;
int ret;
BUG_ON(ensure_size && min_stripe_size == 0);
/*
* The logical here is simplified to handle special cases only
* So we don't need to consider merge case for ensure_size
*/
BUG_ON(min_stripe_size && (min_stripe_size < len * 2 ||
min_stripe_size / 2 < BTRFS_STRIPE_LEN));
/* Also, wipe range should already be aligned */
BUG_ON(start != round_down(start, BTRFS_STRIPE_LEN) ||
start + len != round_up(start + len, BTRFS_STRIPE_LEN));
min_stripe_size /= 2;
cache = lookup_cache_extent(tree, start, len);
if (!cache)
return 0;
if (start <= cache->start) {
/*
* |--------cache---------|
* |-wipe-|
*/
BUG_ON(start + len <= cache->start);
/*
* The wipe size is smaller than min_stripe_size / 2,
* so the result length should still meet min_stripe_size
* And no need to do alignment
*/
cache->size -= (start + len - cache->start);
if (cache->size == 0) {
remove_cache_extent(tree, cache);
free(cache);
return 0;
}
BUG_ON(ensure_size && cache->size < min_stripe_size);
cache->start = start + len;
return 0;
} else if (start > cache->start && start + len < cache->start +
cache->size) {
/*
* |-------cache-----|
* |-wipe-|
*/
u64 old_start = cache->start;
u64 old_len = cache->size;
u64 insert_start = start + len;
u64 insert_len;
cache->size = start - cache->start;
/* Expand the leading half part if needed */
if (ensure_size && cache->size < min_stripe_size) {
ret = _expand_extent_cache(tree, cache,
min_stripe_size, 1);
if (ret < 0)
return ret;
}
/* And insert the new one */
insert_len = old_start + old_len - start - len;
ret = add_merge_cache_extent(tree, insert_start, insert_len);
if (ret < 0)
return ret;
/* Expand the last half part if needed */
if (ensure_size && insert_len < min_stripe_size) {
cache = lookup_cache_extent(tree, insert_start,
insert_len);
if (!cache || cache->start != insert_start ||
cache->size != insert_len)
return -ENOENT;
ret = _expand_extent_cache(tree, cache,
min_stripe_size, 0);
}
return ret;
}
/*
* |----cache-----|
* |--wipe-|
* Wipe len should be small enough and no need to expand the
* remaining extent
*/
cache->size = start - cache->start;
BUG_ON(ensure_size && cache->size < min_stripe_size);
return 0;
}
/*
* Remove reserved ranges from given cache_tree
*
* It will remove the following ranges
* 1) 0~1M
* 2) 2nd superblock, +64K (make sure chunks are 64K aligned)
* 3) 3rd superblock, +64K
*
* @min_stripe must be given for safety check
* and if @ensure_size is given, it will ensure affected cache_extent will be
* larger than min_stripe_size
*/
static int wipe_reserved_ranges(struct cache_tree *tree, u64 min_stripe_size,
int ensure_size)
{
int ret;
ret = wipe_one_reserved_range(tree, 0, 1024 * 1024, min_stripe_size,
ensure_size);
if (ret < 0)
return ret;
ret = wipe_one_reserved_range(tree, btrfs_sb_offset(1),
BTRFS_STRIPE_LEN, min_stripe_size, ensure_size);
if (ret < 0)
return ret;
ret = wipe_one_reserved_range(tree, btrfs_sb_offset(2),
BTRFS_STRIPE_LEN, min_stripe_size, ensure_size);
return ret;
}
static int calculate_available_space(struct btrfs_convert_context *cctx)
{
struct cache_tree *used = &cctx->used;
struct cache_tree *data_chunks = &cctx->data_chunks;
struct cache_tree *free = &cctx->free;
struct cache_extent *cache;
u64 cur_off = 0;
/*
* Twice the minimal chunk size, to allow later wipe_reserved_ranges()
* works without need to consider overlap
*/
u64 min_stripe_size = 2 * 16 * 1024 * 1024;
int ret;
/* Calculate data_chunks */
for (cache = first_cache_extent(used); cache;
cache = next_cache_extent(cache)) {
u64 cur_len;
if (cache->start + cache->size < cur_off)
continue;
if (cache->start > cur_off + min_stripe_size)
cur_off = cache->start;
cur_len = max(cache->start + cache->size - cur_off,
min_stripe_size);
ret = add_merge_cache_extent(data_chunks, cur_off, cur_len);
if (ret < 0)
goto out;
cur_off += cur_len;
}
/*
* remove reserved ranges, so we won't ever bother relocating an old
* filesystem extent to other place.
*/
ret = wipe_reserved_ranges(data_chunks, min_stripe_size, 1);
if (ret < 0)
goto out;
cur_off = 0;
/*
* Calculate free space
* Always round up the start bytenr, to avoid metadata extent corss
* stripe boundary, as later mkfs_convert() won't have all the extent
* allocation check
*/
for (cache = first_cache_extent(data_chunks); cache;
cache = next_cache_extent(cache)) {
if (cache->start < cur_off)
continue;
if (cache->start > cur_off) {
u64 insert_start;
u64 len;
len = cache->start - round_up(cur_off,
BTRFS_STRIPE_LEN);
insert_start = round_up(cur_off, BTRFS_STRIPE_LEN);
ret = add_merge_cache_extent(free, insert_start, len);
if (ret < 0)
goto out;
}
cur_off = cache->start + cache->size;
}
/* Don't forget the last range */
if (cctx->total_bytes > cur_off) {
u64 len = cctx->total_bytes - cur_off;
u64 insert_start;
insert_start = round_up(cur_off, BTRFS_STRIPE_LEN);
ret = add_merge_cache_extent(free, insert_start, len);
if (ret < 0)
goto out;
}
/* Remove reserved bytes */
ret = wipe_reserved_ranges(free, min_stripe_size, 0);
out:
return ret;
}
/*
* Read used space, and since we have the used space,
* calcuate data_chunks and free for later mkfs
*/
static int convert_read_used_space(struct btrfs_convert_context *cctx)
{
int ret;
ret = cctx->convert_ops->read_used_space(cctx);
if (ret)
return ret;
ret = calculate_available_space(cctx);
return ret;
}
/*
* Create the fs image file of old filesystem.
*
* This is completely fs independent as we have cctx->used, only
* need to create file extents pointing to all the positions.
*/
static int create_image(struct btrfs_root *root,
struct btrfs_mkfs_config *cfg,
struct btrfs_convert_context *cctx, int fd,
u64 size, char *name, int datacsum)
{
struct btrfs_inode_item buf;
struct btrfs_trans_handle *trans;
struct btrfs_path path;
struct btrfs_key key;
struct cache_extent *cache;
struct cache_tree used_tmp;
u64 cur;
u64 ino;
u64 flags = BTRFS_INODE_READONLY;
int ret;
if (!datacsum)
flags |= BTRFS_INODE_NODATASUM;
trans = btrfs_start_transaction(root, 1);
if (!trans)
return -ENOMEM;
cache_tree_init(&used_tmp);
btrfs_init_path(&path);
ret = btrfs_find_free_objectid(trans, root, BTRFS_FIRST_FREE_OBJECTID,
&ino);
if (ret < 0)
goto out;
ret = btrfs_new_inode(trans, root, ino, 0400 | S_IFREG);
if (ret < 0)
goto out;
ret = btrfs_change_inode_flags(trans, root, ino, flags);
if (ret < 0)
goto out;
ret = btrfs_add_link(trans, root, ino, BTRFS_FIRST_FREE_OBJECTID, name,
strlen(name), BTRFS_FT_REG_FILE, NULL, 1);
if (ret < 0)
goto out;
key.objectid = ino;
key.type = BTRFS_INODE_ITEM_KEY;
key.offset = 0;
ret = btrfs_search_slot(trans, root, &key, &path, 0, 1);
if (ret) {
ret = (ret > 0 ? -ENOENT : ret);
goto out;
}
read_extent_buffer(path.nodes[0], &buf,
btrfs_item_ptr_offset(path.nodes[0], path.slots[0]),
sizeof(buf));
btrfs_release_path(&path);
/*
* Create a new used space cache, which doesn't contain the reserved
* range
*/
for (cache = first_cache_extent(&cctx->used); cache;
cache = next_cache_extent(cache)) {
ret = add_cache_extent(&used_tmp, cache->start, cache->size);
if (ret < 0)
goto out;
}
ret = wipe_reserved_ranges(&used_tmp, 0, 0);
if (ret < 0)
goto out;
/*
* Start from 1M, as 0~1M is reserved, and create_image_file_range()
* can't handle bytenr 0(will consider it as a hole)
*/
cur = 1024 * 1024;
while (cur < size) {
u64 len = size - cur;
ret = create_image_file_range(trans, root, &used_tmp,
&buf, ino, cur, &len, datacsum);
if (ret < 0)
goto out;
cur += len;
}
/* Handle the reserved ranges */
ret = migrate_reserved_ranges(trans, root, &cctx->used, &buf, fd, ino,
cfg->num_bytes, datacsum);
key.objectid = ino;
key.type = BTRFS_INODE_ITEM_KEY;
key.offset = 0;
ret = btrfs_search_slot(trans, root, &key, &path, 0, 1);
if (ret) {
ret = (ret > 0 ? -ENOENT : ret);
goto out;
}
btrfs_set_stack_inode_size(&buf, cfg->num_bytes);
write_extent_buffer(path.nodes[0], &buf,
btrfs_item_ptr_offset(path.nodes[0], path.slots[0]),
sizeof(buf));
out:
free_extent_cache_tree(&used_tmp);
btrfs_release_path(&path);
btrfs_commit_transaction(trans, root);
return ret;
}
static 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[BTRFS_NAME_LEN + 1]; /* for snprintf null */
int len;
int i;
int ret;
len = strlen(base);
if (len == 0 || len > BTRFS_NAME_LEN)
return NULL;
btrfs_init_path(&path);
key.objectid = dirid;
key.type = BTRFS_DIR_INDEX_KEY;
key.offset = (u64)-1;
ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
if (ret <= 0) {
error("search for DIR_INDEX dirid %llu failed: %d",
(unsigned long long)dirid, ret);
goto fail;
}
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(&path);
trans = btrfs_start_transaction(root, 1);
if (!trans) {
error("unable to start transaction");
goto fail;
}
key.objectid = dirid;
key.offset = 0;
key.type = BTRFS_INODE_ITEM_KEY;
ret = btrfs_lookup_inode(trans, root, &path, &key, 1);
if (ret) {
error("search for INODE_ITEM %llu failed: %d",
(unsigned long long)dirid, ret);
goto fail;
}
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;
memcpy(buf, base, len);
for (i = 0; i < 1024; i++) {
ret = btrfs_insert_dir_item(trans, root, buf, len,
dirid, &key, BTRFS_FT_DIR, index);
if (ret != -EEXIST)
break;
len = snprintf(buf, ARRAY_SIZE(buf), "%s%d", base, i);
if (len < 1 || len > BTRFS_NAME_LEN) {
ret = -EINVAL;
break;
}
}
if (ret)
goto fail;
btrfs_set_inode_size(leaf, inode_item, len * 2 +
btrfs_inode_size(leaf, inode_item));
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(&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, len);
if (ret) {
error("unable to add root backref for %llu: %d",
root->root_key.objectid, ret);
goto fail;
}
/* 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, len);
if (ret) {
error("unable to add root ref for %llu: %d",
root->root_key.objectid, ret);
goto fail;
}
ret = btrfs_commit_transaction(trans, root);
if (ret) {
error("transaction commit failed: %d", ret);
goto fail;
}
new_root = btrfs_read_fs_root(fs_info, &key);
if (IS_ERR(new_root)) {
error("unable to fs read root: %lu", PTR_ERR(new_root));
new_root = NULL;
}
fail:
btrfs_init_path(&path);
return new_root;
}
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);
if (ret)
return 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);
if (!new_root || IS_ERR(new_root)) {
error("unable to fs read root: %lu", PTR_ERR(new_root));
return PTR_ERR(new_root);
}
ret = btrfs_make_root_dir(trans, new_root, BTRFS_FIRST_FREE_OBJECTID);
return ret;
}
/*
* New make_btrfs() has handle system and meta chunks quite well.
* So only need to add remaining data chunks.
*/
static int make_convert_data_block_groups(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
struct btrfs_mkfs_config *cfg,
struct btrfs_convert_context *cctx)
{
struct btrfs_root *extent_root = fs_info->extent_root;
struct cache_tree *data_chunks = &cctx->data_chunks;
struct cache_extent *cache;
u64 max_chunk_size;
int ret = 0;
/*
* Don't create data chunk over 10% of the convert device
* And for single chunk, don't create chunk larger than 1G.
*/
max_chunk_size = cfg->num_bytes / 10;
max_chunk_size = min((u64)(1024 * 1024 * 1024), max_chunk_size);
max_chunk_size = round_down(max_chunk_size, extent_root->sectorsize);
for (cache = first_cache_extent(data_chunks); cache;
cache = next_cache_extent(cache)) {
u64 cur = cache->start;
while (cur < cache->start + cache->size) {
u64 len;
u64 cur_backup = cur;
len = min(max_chunk_size,
cache->start + cache->size - cur);
ret = btrfs_alloc_data_chunk(trans, extent_root,
&cur_backup, len,
BTRFS_BLOCK_GROUP_DATA, 1);
if (ret < 0)
break;
ret = btrfs_make_block_group(trans, extent_root, 0,
BTRFS_BLOCK_GROUP_DATA,
BTRFS_FIRST_CHUNK_TREE_OBJECTID,
cur, len);
if (ret < 0)
break;
cur += len;
}
}
return ret;
}
/*
* Init the temp btrfs to a operational status.
*
* It will fix the extent usage accounting(XXX: Do we really need?) and
* insert needed data chunks, to ensure all old fs data extents are covered
* by DATA chunks, preventing wrong chunks are allocated.
*
* And also create convert image subvolume and relocation tree.
* (XXX: Not need again?)
* But the convert image subvolume is *NOT* linked to fs tree yet.
*/
static int init_btrfs(struct btrfs_mkfs_config *cfg, struct btrfs_root *root,
struct btrfs_convert_context *cctx, int datacsum,
int packing, int noxattr)
{
struct btrfs_key location;
struct btrfs_trans_handle *trans;
struct btrfs_fs_info *fs_info = root->fs_info;
int ret;
/*
* Don't alloc any metadata/system chunk, as we don't want
* any meta/sys chunk allcated before all data chunks are inserted.
* Or we screw up the chunk layout just like the old implement.
*/
fs_info->avoid_sys_chunk_alloc = 1;
fs_info->avoid_meta_chunk_alloc = 1;
trans = btrfs_start_transaction(root, 1);
if (!trans) {
error("unable to start transaction");
ret = -EINVAL;
goto err;
}
ret = btrfs_fix_block_accounting(trans, root);
if (ret)
goto err;
ret = make_convert_data_block_groups(trans, fs_info, cfg, cctx);
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 fs image file */
ret = create_subvol(trans, root, CONV_IMAGE_SUBVOL_OBJECTID);
if (ret < 0) {
error("failed to create subvolume image root: %d", ret);
goto err;
}
/* subvol for data relocation tree */
ret = create_subvol(trans, root, BTRFS_DATA_RELOC_TREE_OBJECTID);
if (ret < 0) {
error("failed to create DATA_RELOC root: %d", ret);
goto err;
}
ret = btrfs_commit_transaction(trans, root);
fs_info->avoid_sys_chunk_alloc = 0;
fs_info->avoid_meta_chunk_alloc = 0;
err:
return ret;
}
/*
* Migrate super block to its default position and zero 0 ~ 16k
*/
static int migrate_super_block(int fd, u64 old_bytenr)
{
int ret;
struct extent_buffer *buf;
struct btrfs_super_block *super;
u32 len;
u32 bytenr;
buf = malloc(sizeof(*buf) + BTRFS_SUPER_INFO_SIZE);
if (!buf)
return -ENOMEM;
buf->len = BTRFS_SUPER_INFO_SIZE;
ret = pread(fd, buf->data, BTRFS_SUPER_INFO_SIZE, old_bytenr);
if (ret != BTRFS_SUPER_INFO_SIZE)
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, BTRFS_SUPER_INFO_SIZE,
BTRFS_SUPER_INFO_OFFSET);
if (ret != BTRFS_SUPER_INFO_SIZE)
goto fail;
ret = fsync(fd);
if (ret)
goto fail;
memset(buf->data, 0, BTRFS_SUPER_INFO_SIZE);
for (bytenr = 0; bytenr < BTRFS_SUPER_INFO_OFFSET; ) {
len = BTRFS_SUPER_INFO_OFFSET - bytenr;
if (len > BTRFS_SUPER_INFO_SIZE)
len = BTRFS_SUPER_INFO_SIZE;
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, BTRFS_STRIPE_LEN);
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;
btrfs_set_stack_stripe_offset(&chunk->stripe, 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;
}
#if BTRFSCONVERT_EXT2
/*
* Open Ext2fs in readonly mode, read block allocation bitmap and
* inode bitmap into memory.
*/
static int ext2_open_fs(struct btrfs_convert_context *cctx, const char *name)
{
errcode_t ret;
ext2_filsys ext2_fs;
ext2_ino_t ino;
u32 ro_feature;
ret = ext2fs_open(name, 0, 0, 0, unix_io_manager, &ext2_fs);
if (ret) {
fprintf(stderr, "ext2fs_open: %s\n", error_message(ret));
return -1;
}
/*
* We need to know exactly the used space, some RO compat flags like
* BIGALLOC will affect how used space is present.
* So we need manuall check any unsupported RO compat flags
*/
ro_feature = ext2_fs->super->s_feature_ro_compat;
if (ro_feature & ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP) {
error(
"unsupported RO features detected: %x, abort convert to avoid possible corruption",
ro_feature & ~EXT2_LIB_FEATURE_COMPAT_SUPP);
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);
}
if (!(ext2_fs->super->s_feature_incompat &
EXT2_FEATURE_INCOMPAT_FILETYPE)) {
error("filetype feature is missing");
goto fail;
}
cctx->fs_data = ext2_fs;
cctx->blocksize = ext2_fs->blocksize;
cctx->block_count = ext2_fs->super->s_blocks_count;
cctx->total_bytes = ext2_fs->blocksize * ext2_fs->super->s_blocks_count;
cctx->volume_name = strndup(ext2_fs->super->s_volume_name, 16);
cctx->first_data_block = ext2_fs->super->s_first_data_block;
cctx->inodes_count = ext2_fs->super->s_inodes_count;
cctx->free_inodes_count = ext2_fs->super->s_free_inodes_count;
return 0;
fail:
ext2fs_close(ext2_fs);
return -1;
}
static int __ext2_add_one_block(ext2_filsys fs, char *bitmap,
unsigned long group_nr, struct cache_tree *used)
{
unsigned long offset;
unsigned i;
int ret = 0;
offset = fs->super->s_first_data_block;
offset /= EXT2FS_CLUSTER_RATIO(fs);
offset += group_nr * EXT2_CLUSTERS_PER_GROUP(fs->super);
for (i = 0; i < EXT2_CLUSTERS_PER_GROUP(fs->super); i++) {
if ((i + offset) >= ext2fs_blocks_count(fs->super))
break;
if (ext2fs_test_bit(i, bitmap)) {
u64 start;
start = (i + offset) * EXT2FS_CLUSTER_RATIO(fs);
start *= fs->blocksize;
ret = add_merge_cache_extent(used, start,
fs->blocksize);
if (ret < 0)
break;
}
}
return ret;
}
/*
* Read all used ext2 space into cctx->used cache tree
*/
static int ext2_read_used_space(struct btrfs_convert_context *cctx)
{
ext2_filsys fs = (ext2_filsys)cctx->fs_data;
blk64_t blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block);
struct cache_tree *used_tree = &cctx->used;
char *block_bitmap = NULL;
unsigned long i;
int block_nbytes;
int ret = 0;
block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
/* Shouldn't happen */
BUG_ON(!fs->block_map);
block_bitmap = malloc(block_nbytes);
if (!block_bitmap)
return -ENOMEM;
for (i = 0; i < fs->group_desc_count; i++) {
ret = ext2fs_get_block_bitmap_range(fs->block_map, blk_itr,
block_nbytes * 8, block_bitmap);
if (ret) {
error("fail to get bitmap from ext2, %s",
strerror(-ret));
break;
}
ret = __ext2_add_one_block(fs, block_bitmap, i, used_tree);
if (ret < 0) {
error("fail to build used space tree, %s",
strerror(-ret));
break;
}
blk_itr += EXT2_CLUSTERS_PER_GROUP(fs->super);
}
free(block_bitmap);
return ret;
}
static void ext2_close_fs(struct btrfs_convert_context *cctx)
{
if (cctx->volume_name) {
free(cctx->volume_name);
cctx->volume_name = NULL;
}
ext2fs_close(cctx->fs_data);
}
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 ext2_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 ext2_dir_iterate_proc(ext2_ino_t dir, int entry,
struct ext2_dir_entry *dirent,
int offset, int blocksize,
char *buf,void *priv_data)
{
int ret;
int file_type;
u64 objectid;
char dotdot[] = "..";
struct dir_iterate_data *idata = (struct dir_iterate_data *)priv_data;
int name_len;
name_len = dirent->name_len & 0xFF;
objectid = dirent->inode + INO_OFFSET;
if (!strncmp(dirent->name, dotdot, name_len)) {
if (name_len == 2) {
BUG_ON(idata->parent != 0);
idata->parent = objectid;
}
return 0;
}
if (dirent->inode < EXT2_GOOD_OLD_FIRST_INO)
return 0;
file_type = dirent->name_len >> 8;
BUG_ON(file_type > EXT2_FT_SYMLINK);
ret = convert_insert_dirent(idata->trans, idata->root, dirent->name,
name_len, idata->objectid, objectid,
ext2_filetype_conversion_table[file_type],
idata->index_cnt, idata->inode);
if (ret < 0) {
idata->errcode = ret;
return BLOCK_ABORT;
}
idata->index_cnt++;
return 0;
}
static int ext2_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,
ext2_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 ext2_block_iterate_proc(ext2_filsys fs, blk_t *blocknr,
e2_blkcnt_t blockcnt, blk_t ref_block,
int ref_offset, void *priv_data)
{
int ret;
struct blk_iterate_data *idata;
idata = (struct blk_iterate_data *)priv_data;
ret = block_iterate_proc(*blocknr, blockcnt, idata);
if (ret) {
idata->errcode = ret;
return BLOCK_ABORT;
}
return 0;
}
/*
* traverse file's data blocks, record these data blocks as file extents.
*/
static int ext2_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;
init_blk_iterate_data(&data, trans, root, btrfs_inode, objectid,
datacsum);
err = ext2fs_block_iterate2(ext2_fs, ext2_ino, BLOCK_FLAG_DATA_ONLY,
NULL, ext2_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(&data, data.first_block,
data.disk_block, data.num_blocks);
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(&data, data.first_block, 0,
last_block - data.first_block);
}
fail:
free(buffer);
return ret;
error:
fprintf(stderr, "ext2fs_block_iterate2: %s\n", error_message(err));
return -1;
}
static int ext2_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 = ext2_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
/* 23.2.5 acl_tag_t values */
#define ACL_UNDEFINED_TAG (0x00)
#define ACL_USER_OBJ (0x01)
#define ACL_USER (0x02)
#define ACL_GROUP_OBJ (0x04)
#define ACL_GROUP (0x08)
#define ACL_MASK (0x10)
#define ACL_OTHER (0x20)
/* 23.2.7 ACL qualifier constants */
#define ACL_UNDEFINED_ID ((id_t)-1)
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 ext2_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;
}
strncpy(namebuf, xattr_prefix_table[name_index], XATTR_NAME_MAX);
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:
free(databuf);
return ret;
}
static int ext2_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 = ext2_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 = ext2_copy_single_xattr(trans, root, objectid,
entry, data, datalen);
if (ret)
goto out;
entry = EXT2_EXT_ATTR_NEXT(entry);
}
out:
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 void ext2_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_sequence(dst, 0);
btrfs_set_stack_inode_transid(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]));
}
}
memset(&dst->reserved, 0, sizeof(dst->reserved));
}
static int ext2_check_state(struct btrfs_convert_context *cctx)
{
ext2_filsys fs = cctx->fs_data;
if (!(fs->super->s_state & EXT2_VALID_FS))
return 1;
else if (fs->super->s_state & EXT2_ERROR_FS)
return 1;
else
return 0;
}
/* EXT2_*_FL to BTRFS_INODE_FLAG_* stringification helper */
#define COPY_ONE_EXT2_FLAG(flags, ext2_inode, name) ({ \
if (ext2_inode->i_flags & EXT2_##name##_FL) \
flags |= BTRFS_INODE_##name; \
})
/*
* Convert EXT2_*_FL to corresponding BTRFS_INODE_* flags
*
* Only a subset of EXT_*_FL is supported in btrfs.
*/
static void ext2_convert_inode_flags(struct btrfs_inode_item *dst,
struct ext2_inode *src)
{
u64 flags = 0;
COPY_ONE_EXT2_FLAG(flags, src, APPEND);
COPY_ONE_EXT2_FLAG(flags, src, SYNC);
COPY_ONE_EXT2_FLAG(flags, src, IMMUTABLE);
COPY_ONE_EXT2_FLAG(flags, src, NODUMP);
COPY_ONE_EXT2_FLAG(flags, src, NOATIME);
COPY_ONE_EXT2_FLAG(flags, src, DIRSYNC);
btrfs_set_stack_inode_flags(dst, flags);
}
/*
* copy a single inode. do all the required works, such as cloning
* inode item, creating file extents and creating directory entries.
*/
static int ext2_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_inode_item btrfs_inode;
if (ext2_inode->i_links_count == 0)
return 0;
ext2_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);
}
ext2_convert_inode_flags(&btrfs_inode, ext2_inode);
switch (ext2_inode->i_mode & S_IFMT) {
case S_IFREG:
ret = ext2_create_file_extents(trans, root, objectid,
&btrfs_inode, ext2_fs, ext2_ino, datacsum, packing);
break;
case S_IFDIR:
ret = ext2_create_dir_entries(trans, root, objectid,
&btrfs_inode, ext2_fs, ext2_ino);
break;
case S_IFLNK:
ret = ext2_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 = ext2_copy_extended_attrs(trans, root, objectid,
&btrfs_inode, ext2_fs, ext2_ino);
if (ret)
return ret;
}
return btrfs_insert_inode(trans, root, objectid, &btrfs_inode);
}
/*
* scan ext2's inode bitmap and copy all used inodes.
*/
static int ext2_copy_inodes(struct btrfs_convert_context *cctx,
struct btrfs_root *root,
int datacsum, int packing, int noxattr, struct task_ctx *p)
{
ext2_filsys ext2_fs = cctx->fs_data;
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 = ext2_copy_single_inode(trans, root,
objectid, ext2_fs, ext2_ino,
&ext2_inode, datacsum, packing,
noxattr);
p->cur_copy_inodes++;
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);
ext2fs_close_inode_scan(ext2_scan);
return ret;
}
static const struct btrfs_convert_operations ext2_convert_ops = {
.name = "ext2",
.open_fs = ext2_open_fs,
.read_used_space = ext2_read_used_space,
.copy_inodes = ext2_copy_inodes,
.close_fs = ext2_close_fs,
.check_state = ext2_check_state,
};
#endif
static const struct btrfs_convert_operations *convert_operations[] = {
#if BTRFSCONVERT_EXT2
&ext2_convert_ops,
#endif
};
static int convert_open_fs(const char *devname,
struct btrfs_convert_context *cctx)
{
int i;
memset(cctx, 0, sizeof(*cctx));
for (i = 0; i < ARRAY_SIZE(convert_operations); i++) {
int ret = convert_operations[i]->open_fs(cctx, devname);
if (ret == 0) {
cctx->convert_ops = convert_operations[i];
return ret;
}
}
error("no file system found to convert");
return -1;
}
static int do_convert(const char *devname, int datacsum, int packing,
int noxattr, u32 nodesize, int copylabel, const char *fslabel,
int progress, u64 features)
{
int ret;
int fd = -1;
u32 blocksize;
u64 total_bytes;
struct btrfs_root *root;
struct btrfs_root *image_root;
struct btrfs_convert_context cctx;
struct btrfs_key key;
char *subvol_name = NULL;
struct task_ctx ctx;
char features_buf[64];
struct btrfs_mkfs_config mkfs_cfg;
init_convert_context(&cctx);
ret = convert_open_fs(devname, &cctx);
if (ret)
goto fail;
ret = convert_check_state(&cctx);
if (ret)
warning(
"source filesystem is not clean, running filesystem check is recommended");
ret = convert_read_used_space(&cctx);
if (ret)
goto fail;
blocksize = cctx.blocksize;
total_bytes = (u64)blocksize * (u64)cctx.block_count;
if (blocksize < 4096) {
error("block size is too small: %u < 4096", blocksize);
goto fail;
}
if (btrfs_check_nodesize(nodesize, blocksize, features))
goto fail;
fd = open(devname, O_RDWR);
if (fd < 0) {
error("unable to open %s: %s", devname, strerror(errno));
goto fail;
}
btrfs_parse_features_to_string(features_buf, features);
if (features == BTRFS_MKFS_DEFAULT_FEATURES)
strcat(features_buf, " (default)");
printf("create btrfs filesystem:\n");
printf("\tblocksize: %u\n", blocksize);
printf("\tnodesize: %u\n", nodesize);
printf("\tfeatures: %s\n", features_buf);
mkfs_cfg.label = cctx.volume_name;
mkfs_cfg.num_bytes = total_bytes;
mkfs_cfg.nodesize = nodesize;
mkfs_cfg.sectorsize = blocksize;
mkfs_cfg.stripesize = blocksize;
mkfs_cfg.features = features;
/* New convert need these space */
memset(mkfs_cfg.chunk_uuid, 0, BTRFS_UUID_UNPARSED_SIZE);
memset(mkfs_cfg.fs_uuid, 0, BTRFS_UUID_UNPARSED_SIZE);
ret = make_btrfs(fd, &mkfs_cfg, &cctx);
if (ret) {
error("unable to create initial ctree: %s", strerror(-ret));
goto fail;
}
root = open_ctree_fd(fd, devname, mkfs_cfg.super_bytenr,
OPEN_CTREE_WRITES | OPEN_CTREE_FS_PARTIAL);
if (!root) {
error("unable to open ctree");
goto fail;
}
ret = init_btrfs(&mkfs_cfg, root, &cctx, datacsum, packing, noxattr);
if (ret) {
error("unable to setup the root tree: %d", ret);
goto fail;
}
printf("creating %s image file\n", cctx.convert_ops->name);
ret = asprintf(&subvol_name, "%s_saved", cctx.convert_ops->name);
if (ret < 0) {
error("memory allocation failure for subvolume name: %s_saved",
cctx.convert_ops->name);
goto fail;
}
key.objectid = CONV_IMAGE_SUBVOL_OBJECTID;
key.offset = (u64)-1;
key.type = BTRFS_ROOT_ITEM_KEY;
image_root = btrfs_read_fs_root(root->fs_info, &key);
if (!image_root) {
error("unable to create image subvolume");
goto fail;
}
ret = create_image(image_root, &mkfs_cfg, &cctx, fd,
mkfs_cfg.num_bytes, "image", datacsum);
if (ret) {
error("failed to create %s/image: %d", subvol_name, ret);
goto fail;
}
printf("creating btrfs metadata");
ctx.max_copy_inodes = (cctx.inodes_count - cctx.free_inodes_count);
ctx.cur_copy_inodes = 0;
if (progress) {
ctx.info = task_init(print_copied_inodes, after_copied_inodes,
&ctx);
task_start(ctx.info);
}
ret = copy_inodes(&cctx, root, datacsum, packing, noxattr, &ctx);
if (ret) {
error("error during copy_inodes %d", ret);
goto fail;
}
if (progress) {
task_stop(ctx.info);
task_deinit(ctx.info);
}
image_root = link_subvol(root, subvol_name, CONV_IMAGE_SUBVOL_OBJECTID);
if (!image_root) {
error("unable to link subvolume %s", subvol_name);
goto fail;
}
free(subvol_name);
memset(root->fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
if (copylabel == 1) {
__strncpy_null(root->fs_info->super_copy->label,
cctx.volume_name, BTRFS_LABEL_SIZE - 1);
printf("copy label '%s'\n", root->fs_info->super_copy->label);
} else if (copylabel == -1) {
strcpy(root->fs_info->super_copy->label, fslabel);
printf("set label to '%s'\n", fslabel);
}
ret = close_ctree(root);
if (ret) {
error("close_ctree failed: %d", ret);
goto fail;
}
convert_close_fs(&cctx);
clean_convert_context(&cctx);
/*
* If this step succeed, we get a mountable btrfs. Otherwise
* the source fs is left unchanged.
*/
ret = migrate_super_block(fd, mkfs_cfg.super_bytenr);
if (ret) {
error("unable to migrate super block: %d", ret);
goto fail;
}
root = open_ctree_fd(fd, devname, 0,
OPEN_CTREE_WRITES | OPEN_CTREE_FS_PARTIAL);
if (!root) {
error("unable to open ctree for finalization");
goto fail;
}
root->fs_info->finalize_on_close = 1;
close_ctree(root);
close(fd);
printf("conversion complete");
return 0;
fail:
clean_convert_context(&cctx);
if (fd != -1)
close(fd);
warning(
"an error occurred during conversion, filesystem is partially created but not finalized and not mountable");
return -1;
}
/*
* Check if a non 1:1 mapped chunk can be rolled back.
* For new convert, it's OK while for old convert it's not.
*/
static int may_rollback_chunk(struct btrfs_fs_info *fs_info, u64 bytenr)
{
struct btrfs_block_group_cache *bg;
struct btrfs_key key;
struct btrfs_path path;
struct btrfs_root *extent_root = fs_info->extent_root;
u64 bg_start;
u64 bg_end;
int ret;
bg = btrfs_lookup_first_block_group(fs_info, bytenr);
if (!bg)
return -ENOENT;
bg_start = bg->key.objectid;
bg_end = bg->key.objectid + bg->key.offset;
key.objectid = bg_end;
key.type = BTRFS_METADATA_ITEM_KEY;
key.offset = 0;
btrfs_init_path(&path);
ret = btrfs_search_slot(NULL, extent_root, &key, &path, 0, 0);
if (ret < 0)
return ret;
while (1) {
struct btrfs_extent_item *ei;
ret = btrfs_previous_extent_item(extent_root, &path, bg_start);
if (ret > 0) {
ret = 0;
break;
}
if (ret < 0)
break;
btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
if (key.type == BTRFS_METADATA_ITEM_KEY)
continue;
/* Now it's EXTENT_ITEM_KEY only */
ei = btrfs_item_ptr(path.nodes[0], path.slots[0],
struct btrfs_extent_item);
/*
* Found data extent, means this is old convert must follow 1:1
* mapping.
*/
if (btrfs_extent_flags(path.nodes[0], ei)
& BTRFS_EXTENT_FLAG_DATA) {
ret = -EINVAL;
break;
}
}
btrfs_release_path(&path);
return ret;
}
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, NULL);
if (ret) {
if (ret == -ENOENT) {
/* removed block group at the tail */
if (length == (u64)-1)
break;
/* removed block group in the middle */
goto next;
}
goto fail;
}
num_stripes = multi->num_stripes;
physical = multi->stripes[0].physical;
free(multi);
if (num_stripes != 1) {
error("num stripes for bytenr %llu is not 1", bytenr);
goto fail;
}
/*
* Extra check for new convert, as metadata chunk from new
* convert is much more free than old convert, it doesn't need
* to do 1:1 mapping.
*/
if (physical != bytenr) {
/*
* Check if it's a metadata chunk and has only metadata
* extent.
*/
ret = may_rollback_chunk(info, bytenr);
if (ret < 0)
goto fail;
}
next:
bytenr += length;
if (bytenr >= total_bytes)
break;
}
return 0;
fail:
return -1;
}
static int do_rollback(const char *devname)
{
int fd = -1;
int ret;
int i;
struct btrfs_root *root;
struct btrfs_root *image_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 = NULL;
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) {
error("unable to open %s: %s", devname, strerror(errno));
goto fail;
}
root = open_ctree_fd(fd, devname, 0, OPEN_CTREE_WRITES);
if (!root) {
error("unable to open ctree");
goto fail;
}
ret = may_rollback(root);
if (ret < 0) {
error("unable to do rollback: %d", ret);
goto fail;
}
sectorsize = root->sectorsize;
buf = malloc(sectorsize);
if (!buf) {
error("unable to allocate memory");
goto fail;
}
btrfs_init_path(&path);
key.objectid = CONV_IMAGE_SUBVOL_OBJECTID;
key.type = BTRFS_ROOT_BACKREF_KEY;
key.offset = BTRFS_FS_TREE_OBJECTID;
ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key, &path, 0,
0);
btrfs_release_path(&path);
if (ret > 0) {
error("unable to convert ext2 image subvolume, is it deleted?");
goto fail;
} else if (ret < 0) {
error("unable to open ext2_saved, id %llu: %s",
(unsigned long long)key.objectid, strerror(-ret));
goto fail;
}
key.objectid = CONV_IMAGE_SUBVOL_OBJECTID;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = (u64)-1;
image_root = btrfs_read_fs_root(root->fs_info, &key);
if (!image_root || IS_ERR(image_root)) {
error("unable to open subvolume %llu: %ld",
(unsigned long long)key.objectid, PTR_ERR(image_root));
goto fail;
}
name = "image";
root_dir = btrfs_root_dirid(&root->root_item);
dir = btrfs_lookup_dir_item(NULL, image_root, &path,
root_dir, name, strlen(name), 0);
if (!dir || IS_ERR(dir)) {
error("unable to find file %s: %ld", name, PTR_ERR(dir));
goto fail;
}
leaf = path.nodes[0];
btrfs_dir_item_key_to_cpu(leaf, dir, &key);
btrfs_release_path(&path);
objectid = key.objectid;
ret = btrfs_lookup_inode(NULL, image_root, &path, &key, 0);
if (ret) {
error("unable to find inode item: %d", ret);
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(&path);
key.objectid = objectid;
key.offset = 0;
key.type = BTRFS_EXTENT_DATA_KEY;
ret = btrfs_search_slot(NULL, image_root, &key, &path, 0, 0);
if (ret != 0) {
error("unable to find first file extent: %d", ret);
btrfs_release_path(&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 ||
key.type != 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);
/*
* Here we must take consideration of old and new convert
* behavior.
* For old convert case, sign, there is no consist chunk type
* that will cover the extent. META/DATA/SYS are all possible.
* Just ensure relocate one is in SYS chunk.
* For new convert case, they are all covered by DATA chunk.
*
* So, there is not valid chunk type check for it now.
*/
if (cache1 != cache2)
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(&path);
if (offset < total_bytes) {
error("unable to build extent mapping (offset %llu, total_bytes %llu)",
(unsigned long long)offset,
(unsigned long long)total_bytes);
error("converted filesystem after balance is unable to rollback");
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)) {
error("no backup for the first extent");
goto fail;
}
/* force no allocation from system block group */
root->fs_info->system_allocs = -1;
trans = btrfs_start_transaction(root, 1);
if (!trans) {
error("unable to start transaction");
goto fail;
}
/*
* 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(&path);
}
btrfs_release_path(&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) {
error(
"unable to empty system block group (num_bytes %llu, first_free %llu",
(unsigned long long)num_bytes,
(unsigned long long)first_free);
goto fail;
}
/* create a system chunk that maps the whole device */
ret = prepare_system_chunk_sb(root->fs_info->super_copy);
if (ret) {
error("unable to update system chunk: %d", ret);
goto fail;
}
ret = btrfs_commit_transaction(trans, root);
if (ret) {
error("transaction commit failed: %d", ret);
goto fail;
}
ret = close_ctree(root);
if (ret) {
error("close_ctree failed: %d", 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);
if (ret != sectorsize) {
error("zeroing superblock mirror %d failed: %d",
i, ret);
goto fail;
}
}
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) {
error("reading superblock at %llu failed: %d",
(unsigned long long)bytenr, ret);
goto fail;
}
BUG_ON(ret != sectorsize);
ret = pwrite(fd, buf, sectorsize, start);
if (ret < 0) {
error("writing superblock at %llu failed: %d",
(unsigned long long)start, ret);
goto fail;
}
BUG_ON(ret != sectorsize);
next_sector:
start += sectorsize;
bytenr += sectorsize;
}
}
ret = fsync(fd);
if (ret < 0) {
error("fsync failed: %s", strerror(errno));
goto fail;
}
/*
* finally, overwrite btrfs super block.
*/
ret = pread(fd, buf, sectorsize, sb_bytenr);
if (ret < 0) {
error("reading primary superblock failed: %s",
strerror(errno));
goto fail;
}
BUG_ON(ret != sectorsize);
ret = pwrite(fd, buf, sectorsize, BTRFS_SUPER_INFO_OFFSET);
if (ret < 0) {
error("writing primary superblock failed: %s",
strerror(errno));
goto fail;
}
BUG_ON(ret != sectorsize);
ret = fsync(fd);
if (ret < 0) {
error("fsync failed: %s", strerror(errno));
goto fail;
}
close(fd);
free(buf);
extent_io_tree_cleanup(&io_tree);
printf("rollback complete\n");
return 0;
fail:
if (fd != -1)
close(fd);
free(buf);
error("rollback aborted");
return -1;
}
static void print_usage(void)
{
printf("usage: btrfs-convert [options] device\n");
printf("options:\n");
printf("\t-d|--no-datasum disable data checksum, sets NODATASUM\n");
printf("\t-i|--no-xattr ignore xattrs and ACLs\n");
printf("\t-n|--no-inline disable inlining of small files to metadata\n");
printf("\t-N|--nodesize SIZE set filesystem metadata nodesize\n");
printf("\t-r|--rollback roll back to the original filesystem\n");
printf("\t-l|--label LABEL set filesystem label\n");
printf("\t-L|--copy-label use label from converted filesystem\n");
printf("\t-p|--progress show converting progress (default)\n");
printf("\t-O|--features LIST comma separated list of filesystem features\n");
printf("\t--no-progress show only overview, not the detailed progress\n");
printf("\n");
printf("Supported filesystems:\n");
printf("\text2/3/4: %s\n", BTRFSCONVERT_EXT2 ? "yes" : "no");
}
int main(int argc, char *argv[])
{
int ret;
int packing = 1;
int noxattr = 0;
int datacsum = 1;
u32 nodesize = max_t(u32, sysconf(_SC_PAGESIZE),
BTRFS_MKFS_DEFAULT_NODE_SIZE);
int rollback = 0;
int copylabel = 0;
int usage_error = 0;
int progress = 1;
char *file;
char fslabel[BTRFS_LABEL_SIZE];
u64 features = BTRFS_MKFS_DEFAULT_FEATURES;
while(1) {
enum { GETOPT_VAL_NO_PROGRESS = 256 };
static const struct option long_options[] = {
{ "no-progress", no_argument, NULL,
GETOPT_VAL_NO_PROGRESS },
{ "no-datasum", no_argument, NULL, 'd' },
{ "no-inline", no_argument, NULL, 'n' },
{ "no-xattr", no_argument, NULL, 'i' },
{ "rollback", no_argument, NULL, 'r' },
{ "features", required_argument, NULL, 'O' },
{ "progress", no_argument, NULL, 'p' },
{ "label", required_argument, NULL, 'l' },
{ "copy-label", no_argument, NULL, 'L' },
{ "nodesize", required_argument, NULL, 'N' },
{ "help", no_argument, NULL, GETOPT_VAL_HELP},
{ NULL, 0, NULL, 0 }
};
int c = getopt_long(argc, argv, "dinN:rl:LpO:", long_options, NULL);
if (c < 0)
break;
switch(c) {
case 'd':
datacsum = 0;
break;
case 'i':
noxattr = 1;
break;
case 'n':
packing = 0;
break;
case 'N':
nodesize = parse_size(optarg);
break;
case 'r':
rollback = 1;
break;
case 'l':
copylabel = -1;
if (strlen(optarg) >= BTRFS_LABEL_SIZE) {
warning(
"label too long, trimmed to %d bytes",
BTRFS_LABEL_SIZE - 1);
}
__strncpy_null(fslabel, optarg, BTRFS_LABEL_SIZE - 1);
break;
case 'L':
copylabel = 1;
break;
case 'p':
progress = 1;
break;
case 'O': {
char *orig = strdup(optarg);
char *tmp = orig;
tmp = btrfs_parse_fs_features(tmp, &features);
if (tmp) {
error("unrecognized filesystem feature: %s",
tmp);
free(orig);
exit(1);
}
free(orig);
if (features & BTRFS_FEATURE_LIST_ALL) {
btrfs_list_all_fs_features(
~BTRFS_CONVERT_ALLOWED_FEATURES);
exit(0);
}
if (features & ~BTRFS_CONVERT_ALLOWED_FEATURES) {
char buf[64];
btrfs_parse_features_to_string(buf,
features & ~BTRFS_CONVERT_ALLOWED_FEATURES);
error("features not allowed for convert: %s",
buf);
exit(1);
}
break;
}
case GETOPT_VAL_NO_PROGRESS:
progress = 0;
break;
case GETOPT_VAL_HELP:
default:
print_usage();
return c != GETOPT_VAL_HELP;
}
}
set_argv0(argv);
if (check_argc_exact(argc - optind, 1)) {
print_usage();
return 1;
}
if (rollback && (!datacsum || noxattr || !packing)) {
fprintf(stderr,
"Usage error: -d, -i, -n options do not apply to rollback\n");
usage_error++;
}
if (usage_error) {
print_usage();
return 1;
}
file = argv[optind];
ret = check_mounted(file);
if (ret < 0) {
error("could not check mount status: %s", strerror(-ret));
return 1;
} else if (ret) {
error("%s is mounted", file);
return 1;
}
if (rollback) {
ret = do_rollback(file);
} else {
ret = do_convert(file, datacsum, packing, noxattr, nodesize,
copylabel, fslabel, progress, features);
}
if (ret)
return 1;
return 0;
}
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