xen-blkfront: remove bio splitting.

bios that are re-submitted will pass through blk_queue_split() when
blk_queue_bio() is called, and this will split the bio if necessary.
There is no longer any need to do this splitting in xen-blkfront.

Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
NeilBrown 2017-06-18 14:38:59 +10:00 committed by Jens Axboe
parent b25d52379a
commit 4559fa5519

View File

@ -110,11 +110,6 @@ struct blk_shadow {
unsigned long associated_id;
};
struct split_bio {
struct bio *bio;
atomic_t pending;
};
struct blkif_req {
int error;
};
@ -2000,28 +1995,13 @@ static int blkfront_probe(struct xenbus_device *dev,
return 0;
}
static void split_bio_end(struct bio *bio)
{
struct split_bio *split_bio = bio->bi_private;
if (atomic_dec_and_test(&split_bio->pending)) {
split_bio->bio->bi_phys_segments = 0;
split_bio->bio->bi_status = bio->bi_status;
bio_endio(split_bio->bio);
kfree(split_bio);
}
bio_put(bio);
}
static int blkif_recover(struct blkfront_info *info)
{
unsigned int i, r_index;
unsigned int r_index;
struct request *req, *n;
int rc;
struct bio *bio, *cloned_bio;
unsigned int segs, offset;
int pending, size;
struct split_bio *split_bio;
struct bio *bio;
unsigned int segs;
blkfront_gather_backend_features(info);
/* Reset limits changed by blk_mq_update_nr_hw_queues(). */
@ -2060,34 +2040,6 @@ static int blkif_recover(struct blkfront_info *info)
while ((bio = bio_list_pop(&info->bio_list)) != NULL) {
/* Traverse the list of pending bios and re-queue them */
if (bio_segments(bio) > segs) {
/*
* This bio has more segments than what we can
* handle, we have to split it.
*/
pending = (bio_segments(bio) + segs - 1) / segs;
split_bio = kzalloc(sizeof(*split_bio), GFP_NOIO);
BUG_ON(split_bio == NULL);
atomic_set(&split_bio->pending, pending);
split_bio->bio = bio;
for (i = 0; i < pending; i++) {
offset = (i * segs * XEN_PAGE_SIZE) >> 9;
size = min((unsigned int)(segs * XEN_PAGE_SIZE) >> 9,
(unsigned int)bio_sectors(bio) - offset);
cloned_bio = bio_clone(bio, GFP_NOIO);
BUG_ON(cloned_bio == NULL);
bio_trim(cloned_bio, offset, size);
cloned_bio->bi_private = split_bio;
cloned_bio->bi_end_io = split_bio_end;
submit_bio(cloned_bio);
}
/*
* Now we have to wait for all those smaller bios to
* end, so we can also end the "parent" bio.
*/
continue;
}
/* We don't need to split this bio */
submit_bio(bio);
}