[v14,08/13] dm-zoned: ensure only power of 2 zone sizes are allowed

Commit Message

Pankaj Raghav Sept. 20, 2022, 9:11 a.m. UTC

From: Luis Chamberlain <[e-mail]>

dm-zoned relies on the assumption that the zone size is a
power-of-2(po2) and the zone capacity is same as the zone size.

Ensure only po2 devices can be used as dm-zoned target until a native
support for zoned devices with non-po2 zone size is added.

Reviewed-by: Hannes Reinecke <[e-mail]>
Reviewed-by: Damien Le Moal <[e-mail]>
Reviewed-by: Bart Van Assche <[e-mail]>
Reviewed-by: Mike Snitzer <[e-mail]>
Reviewed-by: Johannes Thumshirn <[e-mail]>
Signed-off-by: Luis Chamberlain <[e-mail]>
Signed-off-by: Pankaj Raghav <[e-mail]>
---
 drivers/md/dm-zoned-target.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Patch

diff --git a/drivers/md/dm-zoned-target.c b/drivers/md/dm-zoned-target.c
index 95b132b52f33..9325bf5dee81 100644
--- a/drivers/md/dm-zoned-target.c
+++ b/drivers/md/dm-zoned-target.c
@@ -792,6 +792,10 @@  static int dmz_fixup_devices(struct dm_target *ti)
 				return -EINVAL;
 			}
 			zone_nr_sectors = bdev_zone_sectors(bdev);
+			if (!is_power_of_2(zone_nr_sectors)) {
+				ti->error = "Zone size is not a power-of-2 number of sectors";
+				return -EINVAL;
+			}
 			zoned_dev->zone_nr_sectors = zone_nr_sectors;
 			zoned_dev->nr_zones = bdev_nr_zones(bdev);
 		}
@@ -804,6 +808,10 @@  static int dmz_fixup_devices(struct dm_target *ti)
 			return -EINVAL;
 		}
 		zoned_dev->zone_nr_sectors = bdev_zone_sectors(bdev);
+		if (!is_power_of_2(zoned_dev->zone_nr_sectors)) {
+			ti->error = "Zone size is not a power-of-2 number of sectors";
+			return -EINVAL;
+		}
 		zoned_dev->nr_zones = bdev_nr_zones(bdev);
 	}