40  *	@tail: The point of buffer consumption
61 	unsigned int tail;  member
128  * @tail: The pipe ring tail pointer
130 static inline bool pipe_empty(unsigned int head, unsigned int tail)  in pipe_empty()  argument
132 	return head == tail;  in pipe_empty()
138  * @tail: The pipe ring tail pointer
140 static inline unsigned int pipe_occupancy(unsigned int head, unsigned int tail)  in pipe_occupancy()  argument
142 	return head - tail;  in pipe_occupancy()
148  * @tail: The pipe ring tail pointer
151 static inline bool pipe_full(unsigned int head, unsigned int tail,  in pipe_full()  argument
154 	return pipe_occupancy(head, tail) >= limit;  in pipe_full()
160  * @tail: The pipe ring tail pointer
163 static inline unsigned int pipe_space_for_user(unsigned int head, unsigned int tail,  in pipe_space_for_user()  argument
168 	p_occupancy = pipe_occupancy(head, tail);  in pipe_space_for_user()