[PATCH V2 12/12] nvmet: use inline bio for passthru fast path

[Chaitanya Kulkarni]

On 9/1/20 10:29, Logan Gunthorpe wrote:
>> +	if (req->transfer_len <= NVMET_MAX_INLINE_DATA_LEN) {
>> +		bio = &req->p.inline_bio;
>> +		bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
>> +	} else {
>> +		bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
>> +	}
>> +
>> +	bio->bi_end_io = nvmet_passthru_bio_done;
>>   	bio->bi_opf = req_op(rq) | op_flags;
>> +	bio->bi_private = req;
> I still think this would be cleaner to just do:
> 
> if (req->transfer_len <= NVMET_MAX_INLINE_DATA_LEN) {
> 	bio = &req->p.inline_bio;
> 	bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
> } else {
> 	bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
>          bio->bi_end_io = bio_put
This is intentionally kept consistent with what we have for bdev-ns.
> }
> 
>>   	for_each_sg(req->sg, sg, req->sg_cnt, i) {
>>   		if (bio_add_pc_page(rq->q, bio, sg_page(sg), sg->length,
>>   				    sg->offset) < sg->length) {
>> -			bio_put(bio);
>> +			nvmet_passthru_bio_done(bio);
> Then just open code this function here...

> Logan
>