block: replace bi_bdev with a gendisk pointer and partitions index

This way we don't need a block_device structure to submit I/O.  The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open.  Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).

For the actual I/O path all that we need is the gendisk, which exists
once per block device.  But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.

Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 8 insertions, 8 deletions

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 72eb97176403..0e1463d0c334 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -607,7 +607,7 @@ static void request_endio(struct bio *bio)
 static void bio_complete(struct search *s)
 {
 	if (s->orig_bio) {
-		struct request_queue *q = bdev_get_queue(s->orig_bio->bi_bdev);
+		struct request_queue *q = s->orig_bio->bi_disk->queue;
 		generic_end_io_acct(q, bio_data_dir(s->orig_bio),
 				    &s->d->disk->part0, s->start_time);
 
@@ -735,7 +735,7 @@ static void cached_dev_read_done(struct closure *cl)
 	if (s->iop.bio) {
 		bio_reset(s->iop.bio);
 		s->iop.bio->bi_iter.bi_sector = s->cache_miss->bi_iter.bi_sector;
-		s->iop.bio->bi_bdev = s->cache_miss->bi_bdev;
+		bio_copy_dev(s->iop.bio, s->cache_miss);
 		s->iop.bio->bi_iter.bi_size = s->insert_bio_sectors << 9;
 		bch_bio_map(s->iop.bio, NULL);
 
@@ -794,7 +794,7 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s,
 	    !(bio->bi_opf & REQ_META) &&
 	    s->iop.c->gc_stats.in_use < CUTOFF_CACHE_READA)
 		reada = min_t(sector_t, dc->readahead >> 9,
-			      bdev_sectors(bio->bi_bdev) - bio_end_sector(bio));
+			      get_capacity(bio->bi_disk) - bio_end_sector(bio));
 
 	s->insert_bio_sectors = min(sectors, bio_sectors(bio) + reada);
 
@@ -820,7 +820,7 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s,
 		goto out_submit;
 
 	cache_bio->bi_iter.bi_sector	= miss->bi_iter.bi_sector;
-	cache_bio->bi_bdev		= miss->bi_bdev;
+	bio_copy_dev(cache_bio, miss);
 	cache_bio->bi_iter.bi_size	= s->insert_bio_sectors << 9;
 
 	cache_bio->bi_end_io	= request_endio;
@@ -919,7 +919,7 @@ static void cached_dev_write(struct cached_dev *dc, struct search *s)
 			struct bio *flush = bio_alloc_bioset(GFP_NOIO, 0,
 							     dc->disk.bio_split);
 
-			flush->bi_bdev	= bio->bi_bdev;
+			bio_copy_dev(flush, bio);
 			flush->bi_end_io = request_endio;
 			flush->bi_private = cl;
 			flush->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
@@ -956,13 +956,13 @@ static blk_qc_t cached_dev_make_request(struct request_queue *q,
 					struct bio *bio)
 {
 	struct search *s;
-	struct bcache_device *d = bio->bi_bdev->bd_disk->private_data;
+	struct bcache_device *d = bio->bi_disk->private_data;
 	struct cached_dev *dc = container_of(d, struct cached_dev, disk);
 	int rw = bio_data_dir(bio);
 
 	generic_start_io_acct(q, rw, bio_sectors(bio), &d->disk->part0);
 
-	bio->bi_bdev = dc->bdev;
+	bio_set_dev(bio, dc->bdev);
 	bio->bi_iter.bi_sector += dc->sb.data_offset;
 
 	if (cached_dev_get(dc)) {
@@ -1072,7 +1072,7 @@ static blk_qc_t flash_dev_make_request(struct request_queue *q,
 {
 	struct search *s;
 	struct closure *cl;
-	struct bcache_device *d = bio->bi_bdev->bd_disk->private_data;
+	struct bcache_device *d = bio->bi_disk->private_data;
 	int rw = bio_data_dir(bio);
 
 	generic_start_io_acct(q, rw, bio_sectors(bio), &d->disk->part0);