btrfs-progs/kernel-shared/uuid-tree.c
Qu Wenruo 8efa8092aa btrfs-progs: move uuid-tree definitions to kernel-shared/uuid-tree.h
Currently we already have a kernel-shared/uuid-tree.c, which is mostly
shared with kernel.

Kernel also has a uuid-tree.h, but we are still using ctree.h for the
header.

Move all the uuid-tree related definitions to kernel-shared/uuid-tree.h,
making future code sync easier.

Signed-off-by: Qu Wenruo <wqu@suse.com>
2024-07-30 20:01:59 +02:00

202 lines
5.2 KiB
C

/*
* Copyright (C) STRATO AG 2013. 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 <stdio.h>
#include <errno.h>
#include <string.h>
#include "kernel-lib/bitops.h"
#include "kernel-shared/accessors.h"
#include "kernel-shared/extent_io.h"
#include "kernel-shared/uapi/btrfs.h"
#include "kernel-shared/uapi/btrfs_tree.h"
#include "kernel-shared/ctree.h"
#include "kernel-shared/messages.h"
#include "kernel-shared/transaction.h"
#include "kernel-shared/uuid-tree.h"
#include "common/messages.h"
#include "common/utils.h"
void btrfs_uuid_to_key(const u8 *uuid, u8 type, struct btrfs_key *key)
{
u64 tmp;
tmp = get_unaligned_le64(uuid);
put_unaligned_64(tmp, &key->objectid);
key->type = type;
tmp = get_unaligned_le64(uuid + sizeof(u64));
put_unaligned_64(tmp, &key->offset);
}
/*
* Search uuid tree - mounted
*
* return -ENOENT for !found, < 0 for errors, or 0 if an item was found
*/
static int btrfs_uuid_tree_lookup_any(int fd, const u8 *uuid, u8 type,
u64 *subid)
{
int ret;
struct btrfs_ioctl_search_args search_arg;
struct btrfs_ioctl_search_header *search_header;
u32 item_size;
__le64 lesubid;
struct btrfs_key key;
btrfs_uuid_to_key(uuid, type, &key);
memset(&search_arg, 0, sizeof(search_arg));
search_arg.key.tree_id = BTRFS_UUID_TREE_OBJECTID;
search_arg.key.min_objectid = key.objectid;
search_arg.key.min_type = type;
search_arg.key.min_offset = key.offset;
search_arg.key.max_objectid = key.objectid;
search_arg.key.max_type = type;
search_arg.key.max_offset = key.offset;
search_arg.key.max_transid = (u64)-1;
search_arg.key.nr_items = 1;
ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &search_arg);
if (ret < 0) {
fprintf(stderr,
"ioctl(BTRFS_IOC_TREE_SEARCH, uuid, key %016llx, UUID_KEY, %016llx) ret=%d, error: %m\n",
(unsigned long long)key.objectid,
(unsigned long long)key.offset, ret);
ret = -ENOENT;
goto out;
}
if (search_arg.key.nr_items < 1) {
ret = -ENOENT;
goto out;
}
search_header = (struct btrfs_ioctl_search_header *)(search_arg.buf);
item_size = btrfs_search_header_len(search_header);
if ((item_size & (sizeof(u64) - 1)) || item_size == 0) {
printf("btrfs: uuid item with illegal size %lu!\n",
(unsigned long)item_size);
ret = -ENOENT;
goto out;
} else {
ret = 0;
}
/* return first stored id */
memcpy(&lesubid, search_header + 1, sizeof(lesubid));
*subid = le64_to_cpu(lesubid);
out:
return ret;
}
int btrfs_lookup_uuid_subvol_item(int fd, const u8 *uuid, u64 *subvol_id)
{
return btrfs_uuid_tree_lookup_any(fd, uuid, BTRFS_UUID_KEY_SUBVOL,
subvol_id);
}
int btrfs_lookup_uuid_received_subvol_item(int fd, const u8 *uuid,
u64 *subvol_id)
{
return btrfs_uuid_tree_lookup_any(fd, uuid,
BTRFS_UUID_KEY_RECEIVED_SUBVOL,
subvol_id);
}
int btrfs_uuid_tree_remove(struct btrfs_trans_handle *trans, u8 *uuid, u8 type,
u64 subid)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *uuid_root = fs_info->uuid_root;
int ret;
struct btrfs_path *path = NULL;
struct btrfs_key key;
struct extent_buffer *eb;
int slot;
unsigned long offset;
u32 item_size;
unsigned long move_dst;
unsigned long move_src;
unsigned long move_len;
if (!uuid_root) {
ret = -EINVAL;
goto out;
}
btrfs_uuid_to_key(uuid, type, &key);
path = btrfs_alloc_path();
if (!path) {
ret = -ENOMEM;
goto out;
}
ret = btrfs_search_slot(trans, uuid_root, &key, path, -1, 1);
if (ret < 0) {
btrfs_warn(fs_info, "error %d while searching for uuid item!",
ret);
goto out;
}
if (ret > 0) {
ret = -ENOENT;
goto out;
}
eb = path->nodes[0];
slot = path->slots[0];
offset = btrfs_item_ptr_offset(eb, slot);
item_size = btrfs_item_size(eb, slot);
if (!IS_ALIGNED(item_size, sizeof(u64))) {
btrfs_warn(fs_info, "uuid item with illegal size %lu!",
(unsigned long)item_size);
ret = -ENOENT;
goto out;
}
while (item_size) {
__le64 read_subid;
read_extent_buffer(eb, &read_subid, offset, sizeof(read_subid));
if (le64_to_cpu(read_subid) == subid)
break;
offset += sizeof(read_subid);
item_size -= sizeof(read_subid);
}
if (!item_size) {
ret = -ENOENT;
goto out;
}
item_size = btrfs_item_size(eb, slot);
if (item_size == sizeof(subid)) {
ret = btrfs_del_item(trans, uuid_root, path);
goto out;
}
move_dst = offset;
move_src = offset + sizeof(subid);
move_len = item_size - (move_src - btrfs_item_ptr_offset(eb, slot));
memmove_extent_buffer(eb, move_dst, move_src, move_len);
btrfs_truncate_item(path, item_size - sizeof(subid), 1);
out:
btrfs_free_path(path);
return ret;
}