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Diffstat (limited to 'include/xen/interface/io/ring.h')
-rw-r--r--include/xen/interface/io/ring.h19
1 files changed, 14 insertions, 5 deletions
diff --git a/include/xen/interface/io/ring.h b/include/xen/interface/io/ring.h
index 2470ec45ebb2..ba4c4274b714 100644
--- a/include/xen/interface/io/ring.h
+++ b/include/xen/interface/io/ring.h
@@ -72,9 +72,8 @@ typedef unsigned int RING_IDX;
* of the shared memory area (PAGE_SIZE, for instance). To initialise
* the front half:
*
- * mytag_front_ring_t front_ring;
- * SHARED_RING_INIT((mytag_sring_t *)shared_page);
- * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
+ * mytag_front_ring_t ring;
+ * XEN_FRONT_RING_INIT(&ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
*
* Initializing the back follows similarly (note that only the front
* initializes the shared ring):
@@ -146,6 +145,11 @@ struct __name##_back_ring { \
#define FRONT_RING_INIT(_r, _s, __size) FRONT_RING_ATTACH(_r, _s, 0, __size)
+#define XEN_FRONT_RING_INIT(r, s, size) do { \
+ SHARED_RING_INIT(s); \
+ FRONT_RING_INIT(r, s, size); \
+} while (0)
+
#define BACK_RING_ATTACH(_r, _s, _i, __size) do { \
(_r)->rsp_prod_pvt = (_i); \
(_r)->req_cons = (_i); \
@@ -170,16 +174,21 @@ struct __name##_back_ring { \
(RING_FREE_REQUESTS(_r) == 0)
/* Test if there are outstanding messages to be processed on a ring. */
-#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
+#define XEN_RING_NR_UNCONSUMED_RESPONSES(_r) \
((_r)->sring->rsp_prod - (_r)->rsp_cons)
-#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
+#define XEN_RING_NR_UNCONSUMED_REQUESTS(_r) ({ \
unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
unsigned int rsp = RING_SIZE(_r) - \
((_r)->req_cons - (_r)->rsp_prod_pvt); \
req < rsp ? req : rsp; \
})
+#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
+ (!!XEN_RING_NR_UNCONSUMED_RESPONSES(_r))
+#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
+ (!!XEN_RING_NR_UNCONSUMED_REQUESTS(_r))
+
/* Direct access to individual ring elements, by index. */
#define RING_GET_REQUEST(_r, _idx) \
(&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))