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authorPatrick McHardy <kaber@trash.net>2011-01-14 14:12:37 +0100
committerPatrick McHardy <kaber@trash.net>2011-01-14 14:12:37 +0100
commit0134e89c7bcc9fde1da962c82a120691e185619f (patch)
tree3e03335cf001019a2687d161e956de4f73379984 /include/xen/interface/io/ring.h
parentc7066f70d9610df0b9406cc635fc09e86136e714 (diff)
parent6faee60a4e82075853a437831768cc9e2e563e4e (diff)
Merge branch 'master' of git://1984.lsi.us.es/net-next-2.6
Conflicts: net/ipv4/route.c Signed-off-by: Patrick McHardy <kaber@trash.net>
Diffstat (limited to 'include/xen/interface/io/ring.h')
-rw-r--r--include/xen/interface/io/ring.h11
1 files changed, 9 insertions, 2 deletions
diff --git a/include/xen/interface/io/ring.h b/include/xen/interface/io/ring.h
index e8cbf431c8c..75271b9a8f6 100644
--- a/include/xen/interface/io/ring.h
+++ b/include/xen/interface/io/ring.h
@@ -24,8 +24,15 @@ typedef unsigned int RING_IDX;
* A ring contains as many entries as will fit, rounded down to the nearest
* power of two (so we can mask with (size-1) to loop around).
*/
-#define __RING_SIZE(_s, _sz) \
- (__RD32(((_sz) - (long)&(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
+#define __CONST_RING_SIZE(_s, _sz) \
+ (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
+ sizeof(((struct _s##_sring *)0)->ring[0])))
+
+/*
+ * The same for passing in an actual pointer instead of a name tag.
+ */
+#define __RING_SIZE(_s, _sz) \
+ (__RD32(((_sz) - (long)&(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
/*
* Macros to make the correct C datatypes for a new kind of ring.