Re: [PATCH RFC 1/7] block: export helper bio_submit_split()

[Yu Kuai <yukuai1@huaweicloud.com>]

Hi,

在 2025/08/25 18:53, Christoph Hellwig 写道:
> On Mon, Aug 25, 2025 at 05:36:54PM +0800, Yu Kuai wrote:
>> From: Yu Kuai <yukuai3@huawei.com>
>>
>> No functional changes are intended, some drivers like mdraid will split
>> bio by internal processing, prepare to unify bio split codes.
> 
> Maybe name the exported helper bio_submit_split_bioset and keep
> bio_submit_split() as a wrapper that passes the default split
> bioset to keep the code a bit tidyer in blk-merge.c?
> 
Sure.

>> +struct bio *bio_submit_split(struct bio *bio, int split_sectors,
>> +			     struct bio_set *bs)
>>   {
>> +	struct bio *split;
>> +
>>   	if (unlikely(split_sectors < 0))
>>   		goto error;
>>   
>> -	if (split_sectors) {
>> -		struct bio *split;
>> +	if (!split_sectors)
>> +		return bio;
>>   
>> -		split = bio_split(bio, split_sectors, GFP_NOIO,
>> -				&bio->bi_bdev->bd_disk->bio_split);
>> -		if (IS_ERR(split)) {
>> -			split_sectors = PTR_ERR(split);
>> -			goto error;
>> -		}
>> -		split->bi_opf |= REQ_NOMERGE;
>> -		blkcg_bio_issue_init(split);
>> -		bio_chain(split, bio);
>> -		trace_block_split(split, bio->bi_iter.bi_sector);
>> -		WARN_ON_ONCE(bio_zone_write_plugging(bio));
>> -		submit_bio_noacct(bio);
> 
> Maybe skip the reformatting which makes this much harder to read?
> If you think it is useful it can be done in a separate patch.
> 
Please ignore this, I'll skip this.

Thanks for the review!
Kuai

> .
>