Re: [PATCH v5] xen: simplify bitmap_to_xenctl_bitmap for little endian

[Jan Beulich <jbeulich@suse.com>]

On 02.04.2025 11:21, Andrew Cooper wrote:
> On 01/04/2025 11:09 am, Jan Beulich wrote:
>> --- a/xen/common/bitmap.c
>> +++ b/xen/common/bitmap.c
>> @@ -359,12 +343,11 @@ static void bitmap_byte_to_long(unsigned
>>  
>>  #elif defined(__LITTLE_ENDIAN)
>>  
>> -static void bitmap_long_to_byte(uint8_t *bp, const unsigned long *lp,
>> -				unsigned int nbits)
>> -{
>> -	memcpy(bp, lp, DIV_ROUND_UP(nbits, BITS_PER_BYTE));
>> -	clamp_last_byte(bp, nbits);
>> -}
>> +#define LITTLE_ENDIAN 1 /* For IS_ENABLED(). */
> 
> I guess I can fix this in my bswap series by giving __LITTLE_ENDIAN the
> value of 1 when it is defined ?

Hmm, that's an option, yes. Yet then I didn't pay close enough attention
to that part of the respective patch in that series, as I was blindly
assuming it to instead be

#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
# define __LITTLE_ENDIAN __ORDER_LITTLE_ENDIAN__
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
# define __BIG_ENDIAN __ORDER_BIG_ENDIAN__
#endif

to keep the values of the symbols unaltered.

> Otherwise, Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

Thanks.

Jan