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authorJens Axboe <jaxboe@fusionio.com>2011-03-01 15:04:39 -0500
committerJens Axboe <jaxboe@fusionio.com>2011-03-01 15:04:39 -0500
commit6fae9c25134baffbeeb20031479e7ff6f6d8eec0 (patch)
treec9ab89992ce5293a43cd455a81dc8a5926a28a5e /include/linux/bitops.h
parentc186794dbb466b45cf40f942f2d09d6d5b4b0e42 (diff)
parentf5412be599602124d2bdd49947b231dd77c0bf99 (diff)
Merge commit 'v2.6.38-rc6' into for-2.6.39/core
Conflicts: block/cfq-iosched.c Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Diffstat (limited to 'include/linux/bitops.h')
-rw-r--r--include/linux/bitops.h11
1 files changed, 11 insertions, 0 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 827cc95711e..2184c6b97ae 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -109,6 +109,17 @@ static inline __u8 ror8(__u8 word, unsigned int shift)
return (word >> shift) | (word << (8 - shift));
}
+/**
+ * sign_extend32 - sign extend a 32-bit value using specified bit as sign-bit
+ * @value: value to sign extend
+ * @index: 0 based bit index (0<=index<32) to sign bit
+ */
+static inline __s32 sign_extend32(__u32 value, int index)
+{
+ __u8 shift = 31 - index;
+ return (__s32)(value << shift) >> shift;
+}
+
static inline unsigned fls_long(unsigned long l)
{
if (sizeof(l) == 4)