On Fri, May 06, 2022 at 10:11:05AM +0200, Pankaj Raghav wrote:
> From: Luis Chamberlain <mcgrof@xxxxxxxxxx>
>
> Today dm-zoned relies on the assumption that you have a zone size
> with a power of 2. Even though the block layer today enforces this
> requirement, these devices do exist and so provide a stop-gap measure
> to ensure these devices cannot be used by mistake
>
> Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
> Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
> Signed-off-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
> ---
> drivers/md/dm-zone.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/md/dm-zone.c b/drivers/md/dm-zone.c
> index 3e7b1fe15..27dc4ddf2 100644
> --- a/drivers/md/dm-zone.c
> +++ b/drivers/md/dm-zone.c
> @@ -231,6 +231,18 @@ static int dm_revalidate_zones(struct mapped_device *md, struct dm_table *t)
> struct request_queue *q = md->queue;
> unsigned int noio_flag;
> int ret;
> + struct block_device *bdev = md->disk->part0;
> + sector_t zone_sectors;
> + char bname[BDEVNAME_SIZE];
> +
> + zone_sectors = bdev_zone_sectors(bdev);
> +
> + if (!is_power_of_2(zone_sectors)) {
is_power_of_2 takes 'unsigned long' and sector_t is u64, so this is not
32bit clean and we had an actual bug where value 1<<48 was not
recognized as power of 2.
> + DMWARN("%s: %s only power of two zone size supported\n",
> + dm_device_name(md),
> + bdevname(bdev, bname));
> + return 1;
> + }
>
> /*
> * Check if something changed. If yes, cleanup the current resources
> --
> 2.25.1
