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authorPaul Mundt <lethal@linux-sh.org>2011-01-06 18:24:07 +0900
committerPaul Mundt <lethal@linux-sh.org>2011-01-06 18:24:07 +0900
commitf862f904d357dc0d3612347a8dbabe6fae037fbb (patch)
treed7f5c2d5f85fd9e1cfc36beae904dc4f9cca04a3 /include/xen/interface/io/ring.h
parent6f09e41d704fe0bc9157a5357480751d39361d01 (diff)
parent3c0eee3fe6a3a1c745379547c7e7c904aa64f6d5 (diff)
downloadlinux-f862f904d357dc0d3612347a8dbabe6fae037fbb.tar.bz2
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 into sh-latest
Conflicts: arch/sh/kernel/cpu/sh2a/clock-sh7201.c Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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.