[PATCH] kernel: add bit rotation helpers for 16 and 8 bit

[PATCH] kernel: add bit rotation helpers for 16 and 8 bit

[Harvey Harrison]

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>
---
Andrew, these will be used to replace some open-coded variants in the
mac80211 code, there are currently no users so it can go in with little
risk.

Randy, CC'd in case I screwed up the kerneldoc.

 include/linux/bitops.h |   40 ++++++++++++++++++++++++++++++++++++++++
 1 files changed, 40 insertions(+), 0 deletions(-)

diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 69c1edb..40d5473 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)
-- 
1.5.4.4.684.g0e08

Re: [PATCH] kernel: add bit rotation helpers for 16 and 8 bit

[Randy Dunlap]

Harvey Harrison wrote:
> 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>
> ---
> Andrew, these will be used to replace some open-coded variants in the
> mac80211 code, there are currently no users so it can go in with little
> risk.
> 
> Randy, CC'd in case I screwed up the kerneldoc.

Looks good.
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>


>  include/linux/bitops.h |   40 ++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 40 insertions(+), 0 deletions(-)
> 
> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
> index 69c1edb..40d5473 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)


-- 
~Randy