OP_I
struct op_inode_info *oi = OP_I(inode);
struct op_inode_info *ent_oi, *oi = OP_I(dir);
ent_oi = OP_I(inode);
struct op_inode_info *oi = OP_I(inode);
kmem_cache_free(op_inode_cachep, OP_I(inode));
oi = OP_I(root_inode);