125 #define FRONT_RING_INIT(_r, _s, __size) do {				\  argument
126     (_r)->req_prod_pvt = 0;						\
127     (_r)->rsp_cons = 0;							\
128     (_r)->nr_ents = __RING_SIZE(_s, __size);				\
129     (_r)->sring = (_s);							\
132 #define BACK_RING_INIT(_r, _s, __size) do {				\  argument
133     (_r)->rsp_prod_pvt = 0;						\
134     (_r)->req_cons = 0;							\
135     (_r)->nr_ents = __RING_SIZE(_s, __size);				\
136     (_r)->sring = (_s);							\
140 #define FRONT_RING_ATTACH(_r, _s, __size) do {				\  argument
141     (_r)->sring = (_s);							\
142     (_r)->req_prod_pvt = (_s)->req_prod;				\
143     (_r)->rsp_cons = (_s)->rsp_prod;					\
144     (_r)->nr_ents = __RING_SIZE(_s, __size);				\
147 #define BACK_RING_ATTACH(_r, _s, __size) do {				\  argument
148     (_r)->sring = (_s);							\
149     (_r)->rsp_prod_pvt = (_s)->rsp_prod;				\
150     (_r)->req_cons = (_s)->req_prod;					\
151     (_r)->nr_ents = __RING_SIZE(_s, __size);				\
155 #define RING_SIZE(_r)							\  argument
156     ((_r)->nr_ents)
159 #define RING_FREE_REQUESTS(_r)						\  argument
160     (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
165 #define RING_FULL(_r)							\  argument
166     (RING_FREE_REQUESTS(_r) == 0)
169 #define RING_HAS_UNCONSUMED_RESPONSES(_r)				\  argument
170     ((_r)->sring->rsp_prod - (_r)->rsp_cons)
172 #define RING_HAS_UNCONSUMED_REQUESTS(_r)				\  argument
174 	unsigned int req = (_r)->sring->req_prod - (_r)->req_cons;	\
175 	unsigned int rsp = RING_SIZE(_r) -				\
176 			   ((_r)->req_cons - (_r)->rsp_prod_pvt);	\
181 #define RING_GET_REQUEST(_r, _idx)					\  argument
182     (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
193 #define RING_COPY_REQUEST(_r, _idx, _req) do {				\  argument
195 	*(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx);	\
198 #define RING_GET_RESPONSE(_r, _idx)					\  argument
199     (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
202 #define RING_REQUEST_CONS_OVERFLOW(_r, _cons)				\  argument
203     (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
206 #define RING_REQUEST_PROD_OVERFLOW(_r, _prod)               \  argument
207     (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
210 #define RING_PUSH_REQUESTS(_r) do {					\  argument
212     (_r)->sring->req_prod = (_r)->req_prod_pvt;				\
215 #define RING_PUSH_RESPONSES(_r) do {					\  argument
217     (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt;				\
250 #define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do {		\  argument
251     RING_IDX __old = (_r)->sring->req_prod;				\
252     RING_IDX __new = (_r)->req_prod_pvt;				\
254     (_r)->sring->req_prod = __new;					\
256     (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) <		\
260 #define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do {		\  argument
261     RING_IDX __old = (_r)->sring->rsp_prod;				\
262     RING_IDX __new = (_r)->rsp_prod_pvt;				\
264     (_r)->sring->rsp_prod = __new;					\
266     (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) <		\
270 #define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do {		\  argument
271     (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r);			\
273     (_r)->sring->req_event = (_r)->req_cons + 1;			\
275     (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r);			\
278 #define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do {		\  argument
279     (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r);			\
281     (_r)->sring->rsp_event = (_r)->rsp_cons + 1;			\
283     (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r);			\