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>

6 files changed, 18 insertions, 19 deletions

diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c
index 35a5a7210e51..61076eda2e6d 100644
--- a/drivers/md/bcache/debug.c
+++ b/drivers/md/bcache/debug.c
@@ -49,7 +49,7 @@ void bch_btree_verify(struct btree *b)
 	v->keys.ops = b->keys.ops;
 
 	bio = bch_bbio_alloc(b->c);
-	bio->bi_bdev		= PTR_CACHE(b->c, &b->key, 0)->bdev;
+	bio_set_dev(bio, PTR_CACHE(b->c, &b->key, 0)->bdev);
 	bio->bi_iter.bi_sector	= PTR_OFFSET(&b->key, 0);
 	bio->bi_iter.bi_size	= KEY_SIZE(&v->key) << 9;
 	bio->bi_opf		= REQ_OP_READ | REQ_META;
diff --git a/drivers/md/bcache/io.c b/drivers/md/bcache/io.c
index 6a9b85095e7b..7e871bdc0097 100644
--- a/drivers/md/bcache/io.c
+++ b/drivers/md/bcache/io.c
@@ -34,7 +34,7 @@ void __bch_submit_bbio(struct bio *bio, struct cache_set *c)
 	struct bbio *b = container_of(bio, struct bbio, bio);
 
 	bio->bi_iter.bi_sector	= PTR_OFFSET(&b->key, 0);
-	bio->bi_bdev		= PTR_CACHE(c, &b->key, 0)->bdev;
+	bio_set_dev(bio, PTR_CACHE(c, &b->key, 0)->bdev);
 
 	b->submit_time_us = local_clock_us();
 	closure_bio_submit(bio, bio->bi_private);
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 0352d05e495c..7e1d1c3ba33a 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -53,7 +53,7 @@ reread:		left = ca->sb.bucket_size - offset;
 
 		bio_reset(bio);
 		bio->bi_iter.bi_sector	= bucket + offset;
-		bio->bi_bdev	= ca->bdev;
+		bio_set_dev(bio, ca->bdev);
 		bio->bi_iter.bi_size	= len << 9;
 
 		bio->bi_end_io	= journal_read_endio;
@@ -452,7 +452,7 @@ static void do_journal_discard(struct cache *ca)
 		bio_set_op_attrs(bio, REQ_OP_DISCARD, 0);
 		bio->bi_iter.bi_sector	= bucket_to_sector(ca->set,
 						ca->sb.d[ja->discard_idx]);
-		bio->bi_bdev		= ca->bdev;
+		bio_set_dev(bio, ca->bdev);
 		bio->bi_iter.bi_size	= bucket_bytes(ca);
 		bio->bi_end_io		= journal_discard_endio;
 
@@ -623,7 +623,7 @@ static void journal_write_unlocked(struct closure *cl)
 
 		bio_reset(bio);
 		bio->bi_iter.bi_sector	= PTR_OFFSET(k, i);
-		bio->bi_bdev	= ca->bdev;
+		bio_set_dev(bio, ca->bdev);
 		bio->bi_iter.bi_size = sectors << 9;
 
 		bio->bi_end_io	= journal_write_endio;
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);
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 8352fad765f6..974d832e54a6 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -257,7 +257,7 @@ void bch_write_bdev_super(struct cached_dev *dc, struct closure *parent)
 	closure_init(cl, parent);
 
 	bio_reset(bio);
-	bio->bi_bdev	= dc->bdev;
+	bio_set_dev(bio, dc->bdev);
 	bio->bi_end_io	= write_bdev_super_endio;
 	bio->bi_private = dc;
 
@@ -303,7 +303,7 @@ void bcache_write_super(struct cache_set *c)
 		SET_CACHE_SYNC(&ca->sb, CACHE_SYNC(&c->sb));
 
 		bio_reset(bio);
-		bio->bi_bdev	= ca->bdev;
+		bio_set_dev(bio, ca->bdev);
 		bio->bi_end_io	= write_super_endio;
 		bio->bi_private = ca;
 
@@ -508,7 +508,7 @@ static void prio_io(struct cache *ca, uint64_t bucket, int op,
 	closure_init_stack(cl);
 
 	bio->bi_iter.bi_sector	= bucket * ca->sb.bucket_size;
-	bio->bi_bdev		= ca->bdev;
+	bio_set_dev(bio, ca->bdev);
 	bio->bi_iter.bi_size	= bucket_bytes(ca);
 
 	bio->bi_end_io	= prio_endio;
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index 42c66e76f05e..c49022a8dc9d 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -181,7 +181,7 @@ static void write_dirty(struct closure *cl)
 	dirty_init(w);
 	bio_set_op_attrs(&io->bio, REQ_OP_WRITE, 0);
 	io->bio.bi_iter.bi_sector = KEY_START(&w->key);
-	io->bio.bi_bdev		= io->dc->bdev;
+	bio_set_dev(&io->bio, io->dc->bdev);
 	io->bio.bi_end_io	= dirty_endio;
 
 	closure_bio_submit(&io->bio, cl);
@@ -250,8 +250,7 @@ static void read_dirty(struct cached_dev *dc)
 		dirty_init(w);
 		bio_set_op_attrs(&io->bio, REQ_OP_READ, 0);
 		io->bio.bi_iter.bi_sector = PTR_OFFSET(&w->key, 0);
-		io->bio.bi_bdev		= PTR_CACHE(dc->disk.c,
-						    &w->key, 0)->bdev;
+		bio_set_dev(&io->bio, PTR_CACHE(dc->disk.c, &w->key, 0)->bdev);
 		io->bio.bi_end_io	= read_dirty_endio;
 
 		if (bio_alloc_pages(&io->bio, GFP_KERNEL))