dm zoned: add metadata pointer to struct dmz_dev

Add a metadata pointer within struct dmz_dev and use it as argument
for blkdev_report_zones() instead of the metadata itself.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

drivers/md/dm-zoned-metadata.c

@@ -1371,8 +1371,8 @@ static int dmz_load_sb(struct dmz_metadata *zmd)
  */
 static int dmz_init_zone(struct blk_zone *blkz, unsigned int num, void *data)
 {
-	struct dmz_metadata *zmd = data;
-	struct dmz_dev *dev = zmd->nr_devs > 1 ? &zmd->dev[1] : &zmd->dev[0];
+	struct dmz_dev *dev = data;
+	struct dmz_metadata *zmd = dev->metadata;
 	int idx = num + dev->zone_offset;
 	struct dm_zone *zone;
 
@@ -1495,8 +1495,12 @@ static int dmz_init_zones(struct dmz_metadata *zmd)
 
 	/* Allocate zone array */
 	zmd->nr_zones = 0;
-	for (i = 0; i < zmd->nr_devs; i++)
-		zmd->nr_zones += zmd->dev[i].nr_zones;
+	for (i = 0; i < zmd->nr_devs; i++) {
+		struct dmz_dev *dev = &zmd->dev[i];
+
+		dev->metadata = zmd;
+		zmd->nr_zones += dev->nr_zones;
+	}
 
 	if (!zmd->nr_zones) {
 		DMERR("(%s): No zones found", zmd->devname);
@@ -1531,7 +1535,7 @@ static int dmz_init_zones(struct dmz_metadata *zmd)
 	 * first randomly writable zone.
 	 */
 	ret = blkdev_report_zones(zoned_dev->bdev, 0, BLK_ALL_ZONES,
-				  dmz_init_zone, zmd);
+				  dmz_init_zone, zoned_dev);
 	if (ret < 0) {
 		DMDEBUG("(%s): Failed to report zones, error %d",
 			zmd->devname, ret);

drivers/md/dm-zoned.h

@@ -45,11 +45,15 @@
 #define dmz_bio_block(bio)	dmz_sect2blk((bio)->bi_iter.bi_sector)
 #define dmz_bio_blocks(bio)	dmz_sect2blk(bio_sectors(bio))
 
+struct dmz_metadata;
+struct dmz_reclaim;
+
 /*
  * Zoned block device information.
  */
 struct dmz_dev {
 	struct block_device	*bdev;
+	struct dmz_metadata	*metadata;
 
 	char			name[BDEVNAME_SIZE];
 	uuid_t			uuid;
@@ -170,9 +174,6 @@ enum {
 #define dmz_dev_debug(dev, format, args...)	\
 	DMDEBUG("(%s): " format, (dev)->name, ## args)
 
-struct dmz_metadata;
-struct dmz_reclaim;
-
 /*
  * Functions defined in dm-zoned-metadata.c
  */