Re: [PATCH v5 11/31] qcow2: Add offset_into_subcluster() and size_to_subclusters()

[Alberto Garcia]

On Tue 05 May 2020 09:42:08 PM CEST, Eric Blake wrote:
> On 5/5/20 12:38 PM, Alberto Garcia wrote:
>> Like offset_into_cluster() and size_to_clusters(), but for
>> subclusters.
>> 
>> Signed-off-by: Alberto Garcia <address@hidden>
>> ---
>>   block/qcow2.h | 10 ++++++++++
>>   1 file changed, 10 insertions(+)
>> 
>> diff --git a/block/qcow2.h b/block/qcow2.h
>> index e68febb15b..8b1ed1cbcf 100644
>> --- a/block/qcow2.h
>> +++ b/block/qcow2.h
>> @@ -537,11 +537,21 @@ static inline int64_t 
>> offset_into_cluster(BDRVQcow2State *s, int64_t offset)
>>       return offset & (s->cluster_size - 1);
>>   }
>>   
>> +static inline int64_t offset_into_subcluster(BDRVQcow2State *s, int64_t 
>> offset)
>> +{
>> +    return offset & (s->subcluster_size - 1);
>> +}
>> +
>>   static inline uint64_t size_to_clusters(BDRVQcow2State *s, uint64_t size)
>>   {
>>       return (size + (s->cluster_size - 1)) >> s->cluster_bits;
>>   }
>
> Pre-existing, but this could use DIV_ROUND_UP.

Yeah but it would be nicer to have a version of the macro optimized for
powers of two.

Berto