dm zoned: replace 'target' pointer in the bio context

Replace the 'target' pointer in the bio context with the
device pointer as this is what's actually used.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

drivers/md/dm-zoned-target.c

@@ -17,7 +17,7 @@
  * Zone BIO context.
  */
 struct dmz_bioctx {
-	struct dmz_target	*target;
+	struct dmz_dev		*dev;
 	struct dm_zone		*zone;
 	struct bio		*bio;
 	refcount_t		ref;
@@ -76,12 +76,13 @@ struct dmz_target {
  */
 static inline void dmz_bio_endio(struct bio *bio, blk_status_t status)
 {
-	struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
+	struct dmz_bioctx *bioctx =
+		dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
 
 	if (status != BLK_STS_OK && bio->bi_status == BLK_STS_OK)
 		bio->bi_status = status;
 	if (bio->bi_status != BLK_STS_OK)
-		bioctx->target->dev->flags |= DMZ_CHECK_BDEV;
+		bioctx->dev->flags |= DMZ_CHECK_BDEV;
 
 	if (refcount_dec_and_test(&bioctx->ref)) {
 		struct dm_zone *zone = bioctx->zone;
@@ -118,14 +119,20 @@ static int dmz_submit_bio(struct dmz_target *dmz, struct dm_zone *zone,
 			  struct bio *bio, sector_t chunk_block,
 			  unsigned int nr_blocks)
 {
-	struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
+	struct dmz_bioctx *bioctx =
+		dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
+	struct dmz_dev *dev = dmz_zone_to_dev(dmz->metadata, zone);
 	struct bio *clone;
 
+	if (dev->flags & DMZ_BDEV_DYING)
+		return -EIO;
+
 	clone = bio_clone_fast(bio, GFP_NOIO, &dmz->bio_set);
 	if (!clone)
 		return -ENOMEM;
 
-	bio_set_dev(clone, dmz->dev->bdev);
+	bio_set_dev(clone, dev->bdev);
+	bioctx->dev = dev;
 	clone->bi_iter.bi_sector =
 		dmz_start_sect(dmz->metadata, zone) + dmz_blk2sect(chunk_block);
 	clone->bi_iter.bi_size = dmz_blk2sect(nr_blocks) << SECTOR_SHIFT;
@@ -218,8 +225,10 @@ static int dmz_handle_read(struct dmz_target *dmz, struct dm_zone *zone,
 
 		if (nr_blocks) {
 			/* Valid blocks found: read them */
-			nr_blocks = min_t(unsigned int, nr_blocks, end_block - chunk_block);
-			ret = dmz_submit_bio(dmz, rzone, bio, chunk_block, nr_blocks);
+			nr_blocks = min_t(unsigned int, nr_blocks,
+					  end_block - chunk_block);
+			ret = dmz_submit_bio(dmz, rzone, bio,
+					     chunk_block, nr_blocks);
 			if (ret)
 				return ret;
 			chunk_block += nr_blocks;
@@ -330,7 +339,8 @@ static int dmz_handle_write(struct dmz_target *dmz, struct dm_zone *zone,
 		 * and the BIO is aligned to the zone write pointer:
 		 * direct write the zone.
 		 */
-		return dmz_handle_direct_write(dmz, zone, bio, chunk_block, nr_blocks);
+		return dmz_handle_direct_write(dmz, zone, bio,
+					       chunk_block, nr_blocks);
 	}
 
 	/*
@@ -383,7 +393,8 @@ static int dmz_handle_discard(struct dmz_target *dmz, struct dm_zone *zone,
 static void dmz_handle_bio(struct dmz_target *dmz, struct dm_chunk_work *cw,
 			   struct bio *bio)
 {
-	struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
+	struct dmz_bioctx *bioctx =
+		dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
 	struct dmz_metadata *zmd = dmz->metadata;
 	struct dm_zone *zone;
 	int ret;
@@ -397,11 +408,6 @@ static void dmz_handle_bio(struct dmz_target *dmz, struct dm_chunk_work *cw,
 
 	dmz_lock_metadata(zmd);
 
-	if (dmz->dev->flags & DMZ_BDEV_DYING) {
-		ret = -EIO;
-		goto out;
-	}
-
 	/*
 	 * Get the data zone mapping the chunk. There may be no
 	 * mapping for read and discard. If a mapping is obtained,
@@ -625,7 +631,6 @@ static int dmz_map(struct dm_target *ti, struct bio *bio)
 {
 	struct dmz_target *dmz = ti->private;
 	struct dmz_metadata *zmd = dmz->metadata;
-	struct dmz_dev *dev = dmz->dev;
 	struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
 	sector_t sector = bio->bi_iter.bi_sector;
 	unsigned int nr_sectors = bio_sectors(bio);
@@ -642,8 +647,6 @@ static int dmz_map(struct dm_target *ti, struct bio *bio)
 		(unsigned long long)dmz_chunk_block(zmd, dmz_bio_block(bio)),
 		(unsigned int)dmz_bio_blocks(bio));
 
-	bio_set_dev(bio, dev->bdev);
-
 	if (!nr_sectors && bio_op(bio) != REQ_OP_WRITE)
 		return DM_MAPIO_REMAPPED;
 
@@ -652,7 +655,7 @@ static int dmz_map(struct dm_target *ti, struct bio *bio)
 		return DM_MAPIO_KILL;
 
 	/* Initialize the BIO context */
-	bioctx->target = dmz;
+	bioctx->dev = NULL;
 	bioctx->zone = NULL;
 	bioctx->bio = bio;
 	refcount_set(&bioctx->ref, 1);
@@ -931,11 +934,12 @@ static void dmz_io_hints(struct dm_target *ti, struct queue_limits *limits)
 static int dmz_prepare_ioctl(struct dm_target *ti, struct block_device **bdev)
 {
 	struct dmz_target *dmz = ti->private;
+	struct dmz_dev *dev = &dmz->dev[0];
 
-	if (!dmz_check_bdev(dmz->dev))
+	if (!dmz_check_bdev(dev))
 		return -EIO;
 
-	*bdev = dmz->dev->bdev;
+	*bdev = dev->bdev;
 
 	return 0;
 }