[PATCH 03/26] block: Introduce bio_straddle_zones() and bio_offset_from_zone_start()

[Damien Le Moal]

Implement the inline helper functions bio_straddle_zones() and
bio_offset_from_zone_start() to respectively test if a BIO crosses a
zone boundary (the start sector and last sector belong to different
zones) and to obtain the oofset from a zone starting sector of a BIO.

Signed-off-by: Damien Le Moal <dlem...@kernel.org>
---
 include/linux/blkdev.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index d7cac3de65b3..0bb897f0501c 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -845,6 +845,12 @@ static inline unsigned int bio_zone_no(struct bio *bio)
        return disk_zone_no(bio->bi_bdev->bd_disk, bio->bi_iter.bi_sector);
 }
 
+static inline bool bio_straddle_zones(struct bio *bio)
+{
+       return bio_zone_no(bio) !=
+               disk_zone_no(bio->bi_bdev->bd_disk, bio_end_sector(bio) - 1);
+}
+
 static inline unsigned int bio_zone_is_seq(struct bio *bio)
 {
        return disk_zone_is_seq(bio->bi_bdev->bd_disk, bio->bi_iter.bi_sector);
@@ -1297,6 +1303,12 @@ static inline sector_t 
bdev_offset_from_zone_start(struct block_device *bdev,
        return sector & (bdev_zone_sectors(bdev) - 1);
 }
 
+static inline sector_t bio_offset_from_zone_start(struct bio *bio)
+{
+       return bdev_offset_from_zone_start(bio->bi_bdev,
+                                          bio->bi_iter.bi_sector);
+}
+
 static inline bool bdev_is_zone_start(struct block_device *bdev,
                                      sector_t sector)
 {
-- 
2.43.0