789 struct tomoyo_io_buffer {  struct
790 	void (*read) (struct tomoyo_io_buffer *);  argument
791 	int (*write) (struct tomoyo_io_buffer *);  argument
792 	__poll_t (*poll) (struct file *file, poll_table *wait);
794 	struct mutex io_sem;
795 	char __user *read_user_buf;
796 	size_t read_user_buf_avail;
797 	struct {
835 	/* Users counter protected by tomoyo_io_buffer_list_lock. */  argument
836 	u8 users;
838 	struct list_head list;