/* 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; u64 key_objectid = 0; u64 key_offset; struct btrfs_ioctl_search_args search_arg; struct btrfs_ioctl_search_header *search_header; u32 item_size; __le64 lesubid; btrfs_uuid_to_key(uuid, &key_objectid, &key_offset); 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.max_objectid = key_objectid; search_arg.key.min_type = type; search_arg.key.max_type = type; search_arg.key.min_offset = key_offset; 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: %s\n", (unsigned long long)key_objectid, (unsigned long long)key_offset, ret, strerror(errno)); 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; }
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; }