+ inode->i_mode = S_IFBLK;
+ inode->i_bdev = bdev;
+ inode->i_rdev = bdev->bd_dev;
+ bdi = blk_get_backing_dev_info(bdev);
+ if (!bdi)
+ bdi = &default_backing_dev_info;
+ mapping = &inode->i_data;
+ mapping->a_ops = &mapping_aops;
+ mapping->backing_dev_info = bdi;
+ mapping_set_gfp_mask(mapping, GFP_KERNEL);
+ btp->pbr_mapping = mapping;
+ return 0;