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, 6 insertions, 6 deletions

diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c
index a4fbd911d566..c0b82136b2d1 100644
--- a/drivers/md/dm-raid1.c
+++ b/drivers/md/dm-raid1.c
@@ -145,7 +145,7 @@ static void dispatch_bios(void *context, struct bio_list *bio_list)
 
 struct dm_raid1_bio_record {
 	struct mirror *m;
-	/* if details->bi_bdev == NULL, details were not saved */
+	/* if details->bi_disk == NULL, details were not saved */
 	struct dm_bio_details details;
 	region_t write_region;
 };
@@ -464,7 +464,7 @@ static sector_t map_sector(struct mirror *m, struct bio *bio)
 
 static void map_bio(struct mirror *m, struct bio *bio)
 {
-	bio->bi_bdev = m->dev->bdev;
+	bio_set_dev(bio, m->dev->bdev);
 	bio->bi_iter.bi_sector = map_sector(m, bio);
 }
 
@@ -1199,7 +1199,7 @@ static int mirror_map(struct dm_target *ti, struct bio *bio)
 	struct dm_raid1_bio_record *bio_record =
 	  dm_per_bio_data(bio, sizeof(struct dm_raid1_bio_record));
 
-	bio_record->details.bi_bdev = NULL;
+	bio_record->details.bi_disk = NULL;
 
 	if (rw == WRITE) {
 		/* Save region for mirror_end_io() handler */
@@ -1266,7 +1266,7 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio,
 		goto out;
 
 	if (unlikely(*error)) {
-		if (!bio_record->details.bi_bdev) {
+		if (!bio_record->details.bi_disk) {
 			/*
 			 * There wasn't enough memory to record necessary
 			 * information for a retry or there was no other
@@ -1291,7 +1291,7 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio,
 			bd = &bio_record->details;
 
 			dm_bio_restore(bd, bio);
-			bio_record->details.bi_bdev = NULL;
+			bio_record->details.bi_disk = NULL;
 			bio->bi_status = 0;
 
 			queue_bio(ms, bio, rw);
@@ -1301,7 +1301,7 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio,
 	}
 
 out:
-	bio_record->details.bi_bdev = NULL;
+	bio_record->details.bi_disk = NULL;
 
 	return DM_ENDIO_DONE;
 }