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authorSage Weil <sage@inktank.com>2013-08-15 11:11:45 -0700
committerSage Weil <sage@inktank.com>2013-08-15 11:11:45 -0700
commitee3e542fec6e69bc9fb668698889a37d93950ddf (patch)
treee74ee766a4764769ef1d3d45d266b4dea64101d3 /include/xen/interface/io/ring.h
parentfe2a801b50c0bb8039d627e5ae1fec249d10ff39 (diff)
parentf1d6e17f540af37bb1891480143669ba7636c4cf (diff)
Merge remote-tracking branch 'linus/master' into testing
Diffstat (limited to 'include/xen/interface/io/ring.h')
-rw-r--r--include/xen/interface/io/ring.h5
1 files changed, 5 insertions, 0 deletions
diff --git a/include/xen/interface/io/ring.h b/include/xen/interface/io/ring.h
index 75271b9a8f6..7d28aff605c 100644
--- a/include/xen/interface/io/ring.h
+++ b/include/xen/interface/io/ring.h
@@ -188,6 +188,11 @@ struct __name##_back_ring { \
#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
(((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
+/* Ill-behaved frontend determination: Can there be this many requests? */
+#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
+ (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
+
+
#define RING_PUSH_REQUESTS(_r) do { \
wmb(); /* back sees requests /before/ updated producer index */ \
(_r)->sring->req_prod = (_r)->req_prod_pvt; \