Re: [PATCH 07/10] block: kill merge_bvec_fn() completely

[Christoph Hellwig <hch@lst.de>]

> -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;
	}