static int change_header_uuid(struct btrfs_root *root, struct extent_buffer *eb) { struct btrfs_fs_info *fs_info = root->fs_info; int same_fsid = 1; int same_chunk_tree_uuid = 1; int ret; same_fsid = !memcmp_extent_buffer(eb, fs_info->new_fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE); same_chunk_tree_uuid = !memcmp_extent_buffer(eb, fs_info->new_chunk_tree_uuid, btrfs_header_chunk_tree_uuid(eb), BTRFS_UUID_SIZE); if (same_fsid && same_chunk_tree_uuid) return 0; if (!same_fsid) write_extent_buffer(eb, fs_info->new_fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE); if (!same_chunk_tree_uuid) write_extent_buffer(eb, fs_info->new_chunk_tree_uuid, btrfs_header_chunk_tree_uuid(eb), BTRFS_UUID_SIZE); ret = write_tree_block(NULL, root, eb); return ret; }
int csum_tree_block_size(struct extent_buffer *buf, u16 csum_size, int verify) { char *result; u32 len; u32 crc = ~(u32)0; result = malloc(csum_size * sizeof(char)); if (!result) return 1; len = buf->len - BTRFS_CSUM_SIZE; crc = crc32c(crc, buf->data + BTRFS_CSUM_SIZE, len); btrfs_csum_final(crc, result); if (verify) { if (memcmp_extent_buffer(buf, result, 0, csum_size)) { printk("checksum verify failed on %llu found %X " "wanted %X\n", (unsigned long long)buf->start, *((int *)result), *((char *)buf->data)); free(result); return 1; } } else { write_extent_buffer(buf, result, 0, csum_size); } free(result); return 0; }
/* * helper function to look at the directory item pointed to by 'path' * this walks through all the entries in a dir item and finds one * for a specific name. */ struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root, struct btrfs_path *path, const char *name, int name_len) { struct btrfs_dir_item *dir_item; unsigned long name_ptr; u32 total_len; u32 cur = 0; u32 this_len; struct extent_buffer *leaf; leaf = path->nodes[0]; dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item); if (verify_dir_item(root, leaf, dir_item)) return NULL; total_len = btrfs_item_size_nr(leaf, path->slots[0]); while (cur < total_len) { this_len = sizeof(*dir_item) + btrfs_dir_name_len(leaf, dir_item) + btrfs_dir_data_len(leaf, dir_item); name_ptr = (unsigned long)(dir_item + 1); if (btrfs_dir_name_len(leaf, dir_item) == name_len && memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0) return dir_item; cur += this_len; dir_item = (struct btrfs_dir_item *)((char *)dir_item + this_len); } return NULL; }
int find_name_in_backref(struct btrfs_path *path, const char * name, int name_len, struct btrfs_inode_ref **ref_ret) { struct extent_buffer *leaf; struct btrfs_inode_ref *ref; unsigned long ptr; unsigned long name_ptr; u32 item_size; u32 cur_offset = 0; int len; leaf = path->nodes[0]; item_size = btrfs_item_size_nr(leaf, path->slots[0]); ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); while (cur_offset < item_size) { ref = (struct btrfs_inode_ref *)(ptr + cur_offset); len = btrfs_inode_ref_name_len(leaf, ref); name_ptr = (unsigned long)(ref + 1); cur_offset += len + sizeof(*ref); if (len != name_len) continue; if (memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0) { *ref_ret = ref; return 1; } } return 0; }
static int change_device_uuid(struct btrfs_root *root, struct extent_buffer *eb, int slot) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_dev_item *di; int ret = 0; di = btrfs_item_ptr(eb, slot, struct btrfs_dev_item); if (!memcmp_extent_buffer(eb, fs_info->new_fsid, (unsigned long)btrfs_device_fsid(di), BTRFS_FSID_SIZE)) return ret; write_extent_buffer(eb, fs_info->new_fsid, (unsigned long)btrfs_device_fsid(di), BTRFS_FSID_SIZE); ret = write_tree_block(NULL, root, eb); return ret; }
int btrfs_del_root_ref(struct btrfs_trans_handle *trans, struct btrfs_root *tree_root, u64 root_id, u64 ref_id, u64 dirid, u64 *sequence, const char *name, int name_len) { struct btrfs_path *path; struct btrfs_root_ref *ref; struct extent_buffer *leaf; struct btrfs_key key; unsigned long ptr; int err = 0; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = root_id; key.type = BTRFS_ROOT_BACKREF_KEY; key.offset = ref_id; again: ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1); BUG_ON(ret < 0); if (ret == 0) { leaf = path->nodes[0]; ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref); WARN_ON(btrfs_root_ref_dirid(leaf, ref) != dirid); WARN_ON(btrfs_root_ref_name_len(leaf, ref) != name_len); ptr = (unsigned long)(ref + 1); WARN_ON(memcmp_extent_buffer(leaf, name, ptr, name_len)); *sequence = btrfs_root_ref_sequence(leaf, ref); ret = btrfs_del_item(trans, tree_root, path); if (ret) { err = ret; goto out; } } else
static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf) { struct btrfs_fs_devices *fs_devices; int ret = 1; if (buf->start != btrfs_header_bytenr(buf)) return ret; fs_devices = root->fs_info->fs_devices; while (fs_devices) { if (!memcmp_extent_buffer(buf, fs_devices->fsid, (unsigned long)btrfs_header_fsid(buf), BTRFS_FSID_SIZE)) { ret = 0; break; } fs_devices = fs_devices->seed; } return ret; }