dm zoned: avoid unnecessary device recalulation for secondary superblock

The secondary superblock must reside on the same device as the primary
superblock, so there is no need to re-calculate the device.
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

@@ -1135,7 +1135,7 @@ static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
 	/* Bad first super block: search for the second one */
 	zmd->sb[1].block = zmd->sb[0].block + zone_nr_blocks;
 	zmd->sb[1].zone = zmd->sb[0].zone + 1;
-	zmd->sb[1].dev = dmz_zone_to_dev(zmd, zmd->sb[1].zone);
+	zmd->sb[1].dev = zmd->sb[0].dev;
 	for (i = 0; i < zmd->nr_rnd_zones - 1; i++) {
 		if (dmz_read_sb(zmd, 1) != 0)
 			break;
@@ -1144,7 +1144,6 @@ static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
 			return 0;
 		}
 		zmd->sb[1].block += zone_nr_blocks;
-		zmd->sb[1].dev = dmz_zone_to_dev(zmd, zmd->sb[1].zone + i);
 	}
 
 	dmz_free_mblock(zmd, mblk);
@@ -1263,7 +1262,7 @@ static int dmz_load_sb(struct dmz_metadata *zmd)
 		if (!zmd->sb[1].zone)
 			zmd->sb[1].zone = zmd->sb[0].zone + zmd->nr_meta_zones;
 		zmd->sb[1].block = dmz_start_block(zmd, zmd->sb[1].zone);
-		zmd->sb[1].dev = dmz_zone_to_dev(zmd, zmd->sb[1].zone);
+		zmd->sb[1].dev = zmd->sb[0].dev;
 		ret = dmz_get_sb(zmd, 1);
 	} else
 		ret = dmz_lookup_secondary_sb(zmd);