block: introduce bdev_zone_no helper

Add a generic bdev_zone_no() helper to calculate zone number for a
given sector in a block device. This helper internally uses disk_zone_no()
to find the zone number.

Use the helper bdev_zone_no() to calculate nr of zones. This lets us
make modifications to the math if needed in one place.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Link: https://lore.kernel.org/r/20230110143635.77300-4-p.raghav@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/nvme/target/zns.c b/drivers/nvme/target/zns.c
index 1254cf57e008ddbb0da7988defba901d84c85e77..7e4292d88016c1b05d8000590807dd16bd75e10c 100644 (file)
--- a/drivers/nvme/target/zns.c
+++ b/drivers/nvme/target/zns.c
@@ -254,8 +254,7 @@ static unsigned long nvmet_req_nr_zones_from_slba(struct nvmet_req *req)
 {
        unsigned int sect = nvmet_lba_to_sect(req->ns, req->cmd->zmr.slba);
 
-       return bdev_nr_zones(req->ns->bdev) -
-               (sect >> ilog2(bdev_zone_sectors(req->ns->bdev)));
+       return bdev_nr_zones(req->ns->bdev) - bdev_zone_no(req->ns->bdev, sect);
 }
 
 static unsigned long get_nr_zones_from_buf(struct nvmet_req *req, u32 bufsize)

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 7822c6f4c7bd34333e13ef503adc852fb7dc929a..89f51d68c68ad66c12e37820b27a97a0ee02cf27 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1288,6 +1288,11 @@ static inline bool bdev_is_zoned(struct block_device *bdev)
        return blk_queue_is_zoned(bdev_get_queue(bdev));
 }
 
+static inline unsigned int bdev_zone_no(struct block_device *bdev, sector_t sec)
+{
+       return disk_zone_no(bdev->bd_disk, sec);
+}
+
 static inline bool bdev_op_is_zoned_write(struct block_device *bdev,
                                          blk_opf_t op)
 {