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author | J. Bruce Fields <bfields@redhat.com> | 2010-12-17 13:29:07 -0500 |
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committer | J. Bruce Fields <bfields@redhat.com> | 2010-12-17 13:29:07 -0500 |
commit | ec66ee3797e5848356cf593c6ec7aabf30a00cf1 (patch) | |
tree | 7ed5c84cc914644ffa1cd1b6a2b45db53fc224e8 /include/xen/interface/io/ring.h | |
parent | 1205065764f2eda3216ebe213143f69891ee3460 (diff) | |
parent | b0c3844d8af6b9f3f18f31e1b0502fbefa2166be (diff) | |
download | op-kernel-dev-ec66ee3797e5848356cf593c6ec7aabf30a00cf1.zip op-kernel-dev-ec66ee3797e5848356cf593c6ec7aabf30a00cf1.tar.gz |
Merge commit 'v2.6.37-rc6' into for-2.6.38
Diffstat (limited to 'include/xen/interface/io/ring.h')
-rw-r--r-- | include/xen/interface/io/ring.h | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/include/xen/interface/io/ring.h b/include/xen/interface/io/ring.h index e8cbf43..75271b9 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. |