Re: [RFC PATCH 01/17] block: make generic_make_request handle arbitrarily sized bios

Christoph Hellwig
2014-12-23T10:16:21Z

> +void blk_queue_split(struct request_queue *q, struct bio **bio,
> + struct bio_set *bs)
> +{
> + struct bio *split;
> +
> + if ((*bio)->bi_rw & REQ_DISCARD)
> + split = blk_bio_discard_split(q, *bio, bs);
> + else if ((*bio)->bi_rw & REQ_WRITE_SAME)
> + split = blk_bio_write_same_split(q, *bio, bs);
> + else
> + split = blk_bio_segment_split(q, *bio, q->bio_split);
> +
> + if (split) {
> + bio_chain(split, *bio);
> + generic_make_request(*bio);
> + *bio = split;
> + }
> +}
> +EXPORT_SYMBOL(blk_queue_split);

I think blk_queue_split needs to explicitly skip BLOCK_PC bios. Those
are SCSI pass through ioctls that we can't split due to their opaque
nature.