block: simplify and export blk_rq_append_bio

The target SCSI passthrough backend is much better served with the low-level
blk_rq_append_bio construct then the helpers built on top of it, so export it.

Also use the opportunity to remove the pointless request_queue argument and
make the code flow a little more readable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Christoph Hellwig 2016-07-19 11:31:51 +02:00 committed by Jens Axboe
parent 0c4de0f33b
commit 98d61d5b1a
4 changed files with 17 additions and 13 deletions

View File

@ -1363,7 +1363,7 @@ struct request *blk_make_request(struct request_queue *q, struct bio *bio,
int ret;
blk_queue_bounce(q, &bounce_bio);
ret = blk_rq_append_bio(q, rq, bounce_bio);
ret = blk_rq_append_bio(rq, bounce_bio);
if (unlikely(ret)) {
blk_put_request(rq);
return ERR_PTR(ret);

View File

@ -9,21 +9,26 @@
#include "blk.h"
int blk_rq_append_bio(struct request_queue *q, struct request *rq,
struct bio *bio)
/*
* Append a bio to a passthrough request. Only works can be merged into
* the request based on the driver constraints.
*/
int blk_rq_append_bio(struct request *rq, struct bio *bio)
{
if (!rq->bio)
blk_rq_bio_prep(q, rq, bio);
else if (!ll_back_merge_fn(q, rq, bio))
return -EINVAL;
else {
if (!rq->bio) {
blk_rq_bio_prep(rq->q, rq, bio);
} else {
if (!ll_back_merge_fn(rq->q, rq, bio))
return -EINVAL;
rq->biotail->bi_next = bio;
rq->biotail = bio;
rq->__data_len += bio->bi_iter.bi_size;
}
return 0;
}
EXPORT_SYMBOL(blk_rq_append_bio);
static int __blk_rq_unmap_user(struct bio *bio)
{
@ -71,7 +76,7 @@ static int __blk_rq_map_user_iov(struct request *rq,
*/
bio_get(bio);
ret = blk_rq_append_bio(q, rq, bio);
ret = blk_rq_append_bio(rq, bio);
if (ret) {
bio_endio(bio);
__blk_rq_unmap_user(orig_bio);
@ -229,7 +234,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
if (do_copy)
rq->cmd_flags |= REQ_COPY_USER;
ret = blk_rq_append_bio(q, rq, bio);
ret = blk_rq_append_bio(rq, bio);
if (unlikely(ret)) {
/* request is too big */
bio_put(bio);

View File

@ -64,8 +64,6 @@ void blk_exit_rl(struct request_list *rl);
void init_request_from_bio(struct request *req, struct bio *bio);
void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
struct bio *bio);
int blk_rq_append_bio(struct request_queue *q, struct request *rq,
struct bio *bio);
void blk_queue_bypass_start(struct request_queue *q);
void blk_queue_bypass_end(struct request_queue *q);
void blk_dequeue_request(struct request *rq);

View File

@ -802,6 +802,7 @@ extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
extern void blk_rq_unprep_clone(struct request *rq);
extern int blk_insert_cloned_request(struct request_queue *q,
struct request *rq);
extern int blk_rq_append_bio(struct request *rq, struct bio *bio);
extern void blk_delay_queue(struct request_queue *, unsigned long);
extern void blk_queue_split(struct request_queue *, struct bio **,
struct bio_set *);