block: Cleanup block device zone helpers

There is no need to conditionally define on CONFIG_BLK_DEV_ZONED the
inline helper functions bdev_nr_zones(), bdev_max_open_zones(),
bdev_max_active_zones() and disk_zone_no() as these function will return
the correct valu in all cases (zoned device or not, including when
CONFIG_BLK_DEV_ZONED is not set). Furthermore, disk_nr_zones()
definition can be simplified as disk->nr_zones is always 0 for regular
block devices.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20240621031506.759397-4-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: damien-lemoal

include/linux/blkdev.h

@@ -673,11 +673,21 @@ static inline bool blk_queue_is_zoned(struct request_queue *q)
 }
 
 #ifdef CONFIG_BLK_DEV_ZONED
-
 static inline unsigned int disk_nr_zones(struct gendisk *disk)
 {
-	return blk_queue_is_zoned(disk->queue) ? disk->nr_zones : 0;
+	return disk->nr_zones;
+}
+bool blk_zone_plug_bio(struct bio *bio, unsigned int nr_segs);
+#else /* CONFIG_BLK_DEV_ZONED */
+static inline unsigned int disk_nr_zones(struct gendisk *disk)
+{
+	return 0;
+}
+static inline bool blk_zone_plug_bio(struct bio *bio, unsigned int nr_segs)
+{
+	return false;
 }
+#endif /* CONFIG_BLK_DEV_ZONED */
 
 static inline unsigned int disk_zone_no(struct gendisk *disk, sector_t sector)
 {
@@ -701,36 +711,6 @@ static inline unsigned int bdev_max_active_zones(struct block_device *bdev)
 	return bdev->bd_disk->queue->limits.max_active_zones;
 }
 
-bool blk_zone_plug_bio(struct bio *bio, unsigned int nr_segs);
-#else /* CONFIG_BLK_DEV_ZONED */
-static inline unsigned int bdev_nr_zones(struct block_device *bdev)
-{
-	return 0;
-}
-
-static inline unsigned int disk_nr_zones(struct gendisk *disk)
-{
-	return 0;
-}
-static inline unsigned int disk_zone_no(struct gendisk *disk, sector_t sector)
-{
-	return 0;
-}
-static inline unsigned int bdev_max_open_zones(struct block_device *bdev)
-{
-	return 0;
-}
-
-static inline unsigned int bdev_max_active_zones(struct block_device *bdev)
-{
-	return 0;
-}
-static inline bool blk_zone_plug_bio(struct bio *bio, unsigned int nr_segs)
-{
-	return false;
-}
-#endif /* CONFIG_BLK_DEV_ZONED */
-
 static inline unsigned int blk_queue_depth(struct request_queue *q)
 {
 	if (q->queue_depth)