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 <[email protected]>
Acked-by: Randy Dunlap <[email protected]>
Cc: Johannes Berg <[email protected]>
Cc: John W. Linville <[email protected]>
Cc: Joe Perches <[email protected]>
Cc: Jiri Benc <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 40 insertions, 0 deletions

diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 69c1edb9fe54..40d54731de7e 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)