block: switch polling to be bio based

Replace the blk_poll interface that requires the caller to keep a queue
and cookie from the submissions with polling based on the bio.

Polling for the bio itself leads to a few advantages:

 - the cookie construction can made entirely private in blk-mq.c
 - the caller does not need to remember the request_queue and cookie
   separately and thus sidesteps their lifetime issues
 - keeping the device and the cookie inside the bio allows to trivially
   support polling BIOs remapping by stacking drivers
 - a lot of code to propagate the cookie back up the submission path can
   be removed entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig
2021-10-12 13:12:24 +02:00
committed by Jens Axboe
parent 19416123ab
commit 3e08773c38
39 changed files with 232 additions and 264 deletions

View File

@@ -58,7 +58,7 @@ struct nfhd_device {
struct gendisk *disk;
};
static blk_qc_t nfhd_submit_bio(struct bio *bio)
static void nfhd_submit_bio(struct bio *bio)
{
struct nfhd_device *dev = bio->bi_bdev->bd_disk->private_data;
struct bio_vec bvec;
@@ -76,7 +76,6 @@ static blk_qc_t nfhd_submit_bio(struct bio *bio)
sec += len;
}
bio_endio(bio);
return BLK_QC_T_NONE;
}
static int nfhd_getgeo(struct block_device *bdev, struct hd_geometry *geo)