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authorDavid S. Miller <davem@davemloft.net>2010-12-27 09:37:05 +0300
committerDavid S. Miller <davem@davemloft.net>2010-12-27 09:37:05 +0300
commit17f7f4d9fcce8f1b75b5f735569309dee7665968 (patch)
tree14d7e49ca0053a0fcab3c33b5023bf3f90c5c08a /include/xen/interface/io/ring.h
parent041110a439e21cd40709ead4ffbfa8034619ad77 (diff)
parentd7c1255a3a21e98bdc64df8ccf005a174d7e6289 (diff)
downloadlinux-17f7f4d9fcce8f1b75b5f735569309dee7665968.tar.xz
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts: net/ipv4/fib_frontend.c
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 e8cbf431c8cc..75271b9a8f61 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.