int write_all_supers(struct btrfs_root *root) { struct list_head *cur; struct list_head *head = &root->fs_info->fs_devices->devices; struct btrfs_device *dev; struct btrfs_super_block *sb; struct btrfs_dev_item *dev_item; int ret; u64 flags; sb = root->fs_info->super_copy; dev_item = &sb->dev_item; list_for_each(cur, head) { dev = list_entry(cur, struct btrfs_device, dev_list); if (!dev->writeable) continue; btrfs_set_stack_device_generation(dev_item, 0); btrfs_set_stack_device_type(dev_item, dev->type); btrfs_set_stack_device_id(dev_item, dev->devid); btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes); btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used); btrfs_set_stack_device_io_align(dev_item, dev->io_align); btrfs_set_stack_device_io_width(dev_item, dev->io_width); btrfs_set_stack_device_sector_size(dev_item, dev->sector_size); memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE); memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE); flags = btrfs_super_flags(sb); btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN); ret = write_dev_supers(root, sb, dev); BUG_ON(ret); }
int btrfs_add_to_fsid(struct btrfs_trans_handle *trans, struct btrfs_root *root, int fd, char *path, u64 block_count, u32 io_width, u32 io_align, u32 sectorsize) { struct btrfs_super_block *disk_super; struct btrfs_super_block *super = root->fs_info->super_copy; struct btrfs_device *device; struct btrfs_dev_item *dev_item; char *buf; u64 total_bytes; u64 num_devs; int ret; device = kzalloc(sizeof(*device), GFP_NOFS); if (!device) return -ENOMEM; buf = kmalloc(sectorsize, GFP_NOFS); if (!buf) { kfree(device); return -ENOMEM; } BUG_ON(sizeof(*disk_super) > sectorsize); memset(buf, 0, sectorsize); disk_super = (struct btrfs_super_block *)buf; dev_item = &disk_super->dev_item; uuid_generate(device->uuid); device->devid = 0; device->type = 0; device->io_width = io_width; device->io_align = io_align; device->sector_size = sectorsize; device->fd = fd; device->writeable = 1; device->total_bytes = block_count; device->bytes_used = 0; device->total_ios = 0; device->dev_root = root->fs_info->dev_root; ret = btrfs_add_device(trans, root, device); BUG_ON(ret); total_bytes = btrfs_super_total_bytes(super) + block_count; btrfs_set_super_total_bytes(super, total_bytes); num_devs = btrfs_super_num_devices(super) + 1; btrfs_set_super_num_devices(super, num_devs); memcpy(disk_super, super, sizeof(*disk_super)); printf("adding device %s id %llu\n", path, (unsigned long long)device->devid); btrfs_set_super_bytenr(disk_super, BTRFS_SUPER_INFO_OFFSET); btrfs_set_stack_device_id(dev_item, device->devid); btrfs_set_stack_device_type(dev_item, device->type); btrfs_set_stack_device_io_align(dev_item, device->io_align); btrfs_set_stack_device_io_width(dev_item, device->io_width); btrfs_set_stack_device_sector_size(dev_item, device->sector_size); btrfs_set_stack_device_total_bytes(dev_item, device->total_bytes); btrfs_set_stack_device_bytes_used(dev_item, device->bytes_used); memcpy(&dev_item->uuid, device->uuid, BTRFS_UUID_SIZE); ret = pwrite(fd, buf, sectorsize, BTRFS_SUPER_INFO_OFFSET); BUG_ON(ret != sectorsize); kfree(buf); list_add(&device->dev_list, &root->fs_info->fs_devices->devices); device->fs_devices = root->fs_info->fs_devices; return 0; }