[Drbd-dev] [PATCH 07/10] block: kill merge_bvec_fn() completely

[Ming Lin]

On Wed, May 6, 2015 at 12:26 AM, Christoph Hellwig <hch at lst.de> wrote:
>> -static int chunk_aligned_read(struct mddev *mddev, struct bio * raid_bio)
>> +static int __chunk_aligned_read(struct mddev *mddev, struct bio *raid_bio)
>
> Call it raid5_read_one_chunk or something similar descriptive?
>
>>  {
>>       struct r5conf *conf = mddev->private;
>>       int dd_idx;
>> @@ -4718,7 +4718,7 @@ static int chunk_aligned_read(struct mddev *mddev, struct bio * raid_bio)
>>       sector_t end_sector;
>>
>>       if (!in_chunk_boundary(mddev, raid_bio)) {
>> -             pr_debug("chunk_aligned_read : non aligned\n");
>> +             pr_debug("__chunk_aligned_read : non aligned\n");
>
> Switch to __func__?
>
>> +static struct bio *chunk_aligned_read(struct mddev *mddev, struct bio *raid_bio)
>> +{
>> +     struct bio *split;
>> +
>> +     do {
>> +             sector_t sector = raid_bio->bi_iter.bi_sector;
>> +             unsigned chunk_sects = mddev->chunk_sectors;
>> +
>> +             unsigned sectors = chunk_sects -
>> +                     (likely(is_power_of_2(chunk_sects))
>> +                      ? (sector & (chunk_sects-1))
>> +                      : sector_div(sector, chunk_sects));
>
> This would be a lot more readable with a good old if.
>
>>       if (rw == READ && mddev->degraded == 0 &&
>>            mddev->reshape_position == MaxSector &&
>> -          chunk_aligned_read(mddev,bi))
>> +          (!(bi = chunk_aligned_read(mddev, bi))))
>>               return;
>
>         if (rw == READ && mddev->degraded == 0 &&
>             mddev->reshape_position == MaxSector) {
>                 bi = chunk_aligned_read(mddev, bi);
>                 if (!bi)
>                         return;
>         }

Will update all. Thanks.