bool blk_integrity_merge_bio(struct request_queue *q, struct request *req,
struct bio *bio)
{
int nr_integrity_segs;
struct bio *next = bio->bi_next;
if (blk_integrity_rq(req) == 0 && bio_integrity(bio) == NULL)
return true;
if (blk_integrity_rq(req) == 0 || bio_integrity(bio) == NULL)
return false;
if (bio_integrity(req->bio)->bip_flags != bio_integrity(bio)->bip_flags)
return false;
bio->bi_next = NULL;
nr_integrity_segs = blk_rq_count_integrity_sg(q, bio);
bio->bi_next = next;
if (req->nr_integrity_segments + nr_integrity_segs >
q->limits.max_integrity_segments)
return false;
req->nr_integrity_segments += nr_integrity_segs;
return true;
}
int blk_integrity_merge_rq(struct request_queue *q, struct request *req,
struct request *next)
{
if (blk_integrity_rq(req) != blk_integrity_rq(next))
return -1;
if (req->nr_integrity_segments + next->nr_integrity_segments >
q->limits.max_integrity_segments)
return -1;
return 0;
}
bool blk_integrity_merge_rq(struct request_queue *q, struct request *req,
struct request *next)
{
if (blk_integrity_rq(req) == 0 && blk_integrity_rq(next) == 0)
return true;
if (blk_integrity_rq(req) == 0 || blk_integrity_rq(next) == 0)
return false;
if (bio_integrity(req->bio)->bip_flags !=
bio_integrity(next->bio)->bip_flags)
return false;
if (req->nr_integrity_segments + next->nr_integrity_segments >
q->limits.max_integrity_segments)
return false;
return true;
}
static int ll_merge_requests_fn(struct request_queue *q, struct request *req,
struct request *next)
{
int total_phys_segments;
unsigned int seg_size =
req->biotail->bi_seg_back_size + next->bio->bi_seg_front_size;
/*
* First check if the either of the requests are re-queued
* requests. Can't merge them if they are.
*/
if (req_no_special_merge(req) || req_no_special_merge(next))
return 0;
/*
* Will it become too large?
*/
if ((blk_rq_sectors(req) + blk_rq_sectors(next)) >
blk_rq_get_max_sectors(req))
return 0;
total_phys_segments = req->nr_phys_segments + next->nr_phys_segments;
if (blk_phys_contig_segment(q, req->biotail, next->bio)) {
if (req->nr_phys_segments == 1)
req->bio->bi_seg_front_size = seg_size;
if (next->nr_phys_segments == 1)
next->biotail->bi_seg_back_size = seg_size;
total_phys_segments--;
}
if (total_phys_segments > queue_max_segments(q))
return 0;
if (blk_integrity_rq(req) && blk_integrity_merge_rq(q, req, next))
return 0;
/* Merge is OK... */
req->nr_phys_segments = total_phys_segments;
return 1;
}
bool blk_rq_merge_ok(struct request *rq, struct bio *bio)
{
struct request_queue *q = rq->q;
if (!rq_mergeable(rq) || !bio_mergeable(bio))
return false;
if (!blk_check_merge_flags(rq->cmd_flags, bio->bi_rw))
return false;
/* different data direction or already started, don't merge */
if (bio_data_dir(bio) != rq_data_dir(rq))
return false;
/* must be same device and not a special request */
if (rq->rq_disk != bio->bi_bdev->bd_disk || req_no_special_merge(rq))
return false;
/* only merge integrity protected bio into ditto rq */
if (bio_integrity(bio) != blk_integrity_rq(rq))
return false;
/* must be using the same buffer */
if (rq->cmd_flags & REQ_WRITE_SAME &&
!blk_write_same_mergeable(rq->bio, bio))
return false;
if (q->queue_flags & (1 << QUEUE_FLAG_SG_GAPS)) {
struct bio_vec *bprev;
bprev = &rq->biotail->bi_io_vec[rq->biotail->bi_vcnt - 1];
if (bvec_gap_to_prev(bprev, bio->bi_io_vec[0].bv_offset))
return false;
}
return true;
}
