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authorHarvey Harrison <harvey.harrison@gmail.com>2008-03-28 14:16:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-03-28 14:45:22 -0700
commit3afe3925987adc3fc052abe404e44520c2072fc8 (patch)
treecf77c295869b10591865898857d5adaae000415c
parent589499c04b9929ce3de9a9cc591f8a24cf1ebc91 (diff)
kernel: add bit rotation helpers for 16 and 8 bit
Will replace open-coded variants elsewhere. Done in the same style as the 32-bit versions. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: John W. Linville <linville@tuxdriver.com> Cc: Joe Perches <joe@perches.com> Cc: Jiri Benc <jbenc@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--include/linux/bitops.h40
1 files changed, 40 insertions, 0 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 69c1edb9fe5..40d54731de7 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -65,6 +65,46 @@ static inline __u32 ror32(__u32 word, unsigned int shift)
return (word >> shift) | (word << (32 - shift));
}
+/**
+ * rol16 - rotate a 16-bit value left
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline __u16 rol16(__u16 word, unsigned int shift)
+{
+ return (word << shift) | (word >> (16 - shift));
+}
+
+/**
+ * ror16 - rotate a 16-bit value right
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline __u16 ror16(__u16 word, unsigned int shift)
+{
+ return (word >> shift) | (word << (16 - shift));
+}
+
+/**
+ * rol8 - rotate an 8-bit value left
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline __u8 rol8(__u8 word, unsigned int shift)
+{
+ return (word << shift) | (word >> (8 - shift));
+}
+
+/**
+ * ror8 - rotate an 8-bit value right
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline __u8 ror8(__u8 word, unsigned int shift)
+{
+ return (word >> shift) | (word << (8 - shift));
+}
+
static inline unsigned fls_long(unsigned long l)
{
if (sizeof(l) == 4)