static int load_chunk_info(int fd, struct chunk_info **info_ptr, int *info_count)
{
int ret;
struct btrfs_ioctl_search_args args;
struct btrfs_ioctl_search_key *sk = &args.key;
struct btrfs_ioctl_search_header *sh;
unsigned long off = 0;
int i, e;
memset(&args, 0, sizeof(args));
/*
* there may be more than one ROOT_ITEM key if there are
* snapshots pending deletion, we have to loop through
* them.
*/
sk->tree_id = BTRFS_CHUNK_TREE_OBJECTID;
sk->min_objectid = 0;
sk->max_objectid = (u64)-1;
sk->max_type = 0;
sk->min_type = (u8)-1;
sk->min_offset = 0;
sk->max_offset = (u64)-1;
sk->min_transid = 0;
sk->max_transid = (u64)-1;
sk->nr_items = 4096;
while (1) {
ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
e = errno;
if (e == EPERM)
return -e;
if (ret < 0) {
error("cannot look up chunk tree info: %s",
strerror(e));
return 1;
}
/* the ioctl returns the number of item it found in nr_items */
if (sk->nr_items == 0)
break;
off = 0;
for (i = 0; i < sk->nr_items; i++) {
struct btrfs_chunk *item;
sh = (struct btrfs_ioctl_search_header *)(args.buf +
off);
off += sizeof(*sh);
item = (struct btrfs_chunk *)(args.buf + off);
ret = add_info_to_list(info_ptr, info_count, item);
if (ret) {
*info_ptr = NULL;
return 1;
}
off += btrfs_search_header_len(sh);
sk->min_objectid = btrfs_search_header_objectid(sh);
sk->min_type = btrfs_search_header_type(sh);
sk->min_offset = btrfs_search_header_offset(sh)+1;
}
if (!sk->min_offset) /* overflow */
sk->min_type++;
else
continue;
if (!sk->min_type)
sk->min_objectid++;
else
continue;
if (!sk->min_objectid)
break;
}
qsort(*info_ptr, *info_count, sizeof(struct chunk_info),
cmp_chunk_info);
return 0;
}
/*
* Enumerate all dead subvolumes that exist in the filesystem.
* Fill @ids and reallocate to bigger size if needed.
*/
static int enumerate_dead_subvols(int fd, u64 **ids)
{
int ret;
struct btrfs_ioctl_search_args args;
struct btrfs_ioctl_search_key *sk = &args.key;
int idx = 0;
int count = 0;
memset(&args, 0, sizeof(args));
sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
sk->min_objectid = BTRFS_ORPHAN_OBJECTID;
sk->max_objectid = BTRFS_ORPHAN_OBJECTID;
sk->min_type = BTRFS_ORPHAN_ITEM_KEY;
sk->max_type = BTRFS_ORPHAN_ITEM_KEY;
sk->min_offset = 0;
sk->max_offset = (u64)-1;
sk->min_transid = 0;
sk->max_transid = (u64)-1;
sk->nr_items = 4096;
*ids = NULL;
while (1) {
struct btrfs_ioctl_search_header *sh;
unsigned long off;
int i;
ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
if (ret < 0)
return -errno;
if (!sk->nr_items)
return idx;
off = 0;
for (i = 0; i < sk->nr_items; i++) {
sh = (struct btrfs_ioctl_search_header*)(args.buf + off);
off += sizeof(*sh);
if (btrfs_search_header_type(sh)
== BTRFS_ORPHAN_ITEM_KEY) {
if (idx >= count) {
u64 *newids;
count += SUBVOL_ID_BATCH;
newids = (u64*)realloc(*ids,
count * sizeof(u64));
if (!newids)
return -ENOMEM;
*ids = newids;
}
(*ids)[idx] = btrfs_search_header_offset(sh);
idx++;
}
off += btrfs_search_header_len(sh);
sk->min_objectid = btrfs_search_header_objectid(sh);
sk->min_type = btrfs_search_header_type(sh);
sk->min_offset = btrfs_search_header_offset(sh);
}
if (sk->min_offset < (u64)-1)
sk->min_offset++;
else
break;
if (sk->min_type != BTRFS_ORPHAN_ITEM_KEY)
break;
if (sk->min_objectid != BTRFS_ORPHAN_OBJECTID)
break;
}
return idx;
}
