Commit 1280d4b7 authored by Uladzislau Koshchanka's avatar Uladzislau Koshchanka Committed by Jakub Kicinski
Browse files

lib: packing: replace bit_reverse() with bitrev8() 



Remove bit_reverse() function.  Instead use bitrev8() from linux/bitrev.h +
bitshift.  Reduces code-repetition.

Signed-off-by: default avatarUladzislau Koshchanka <koshchanka@gmail.com>
Link: https://lore.kernel.org/r/20221210004423.32332-1-koshchanka@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 93e637a3

lib/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ config LINEAR_RANGES 


config PACKING

	bool "Generic bitfield packing and unpacking"

	select BITREVERSE

	default n

	help

	  This option provides the packing() helper function, which permits

lib/packing.c

+2 −14
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
#include <linux/bitops.h>

#include <linux/errno.h>

#include <linux/types.h>

#include <linux/bitrev.h>



static int get_le_offset(int offset)

{
@@ -29,19 +30,6 @@ static int get_reverse_lsw32_offset(int offset, size_t len) 
	return word_index * 4 + offset;

}



static u64 bit_reverse(u64 val, unsigned int width)

{

	u64 new_val = 0;

	unsigned int bit;

	unsigned int i;



	for (i = 0; i < width; i++) {

		bit = (val & (1 << i)) != 0;

		new_val |= (bit << (width - i - 1));

	}

	return new_val;

}



static void adjust_for_msb_right_quirk(u64 *to_write, int *box_start_bit,

				       int *box_end_bit, u8 *box_mask)

{
@@ -49,7 +37,7 @@ static void adjust_for_msb_right_quirk(u64 *to_write, int *box_start_bit, 
	int new_box_start_bit, new_box_end_bit;



	*to_write >>= *box_end_bit;

	*to_write = bit_reverse(*to_write, box_bit_width);

	*to_write = bitrev8(*to_write) >> (8 - box_bit_width);

	*to_write <<= *box_end_bit;



	new_box_end_bit   = box_bit_width - *box_start_bit - 1;