[dm-devel] [PATCH 05/16] nvme: zns: Allow ZNS drives that have non-power_of_2 zone size

[Adam Manzanares]

On Wed, Apr 27, 2022 at 06:02:44PM +0200, Pankaj Raghav wrote:
> Remove the condition which disallows non-power_of_2 zone size ZNS drive
> to be updated and use generic method to calculate number of zones
> instead of relying on log and shift based calculation on zone size.
> 
> The power_of_2 calculation has been replaced directly with generic
> calculation without special handling. Both modified functions are not
> used in hot paths, they are only used during initialization &
> revalidation of the ZNS device.
> 
> Reviewed-by: Luis Chamberlain <mcgrof at kernel.org>
> Signed-off-by: Pankaj Raghav <p.raghav at samsung.com>
> ---
>  drivers/nvme/host/zns.c | 11 ++---------
>  1 file changed, 2 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/nvme/host/zns.c b/drivers/nvme/host/zns.c
> index 9f81beb4df4e..2087de0768ee 100644
> --- a/drivers/nvme/host/zns.c
> +++ b/drivers/nvme/host/zns.c
> @@ -101,13 +101,6 @@ int nvme_update_zone_info(struct nvme_ns *ns, unsigned lbaf)
>  	}
>  
>  	ns->zsze = nvme_lba_to_sect(ns, le64_to_cpu(id->lbafe[lbaf].zsze));
> -	if (!is_power_of_2(ns->zsze)) {
> -		dev_warn(ns->ctrl->device,
> -			"invalid zone size:%llu for namespace:%u\n",
> -			ns->zsze, ns->head->ns_id);
> -		status = -ENODEV;
> -		goto free_data;
> -	}
>  
>  	blk_queue_set_zoned(ns->disk, BLK_ZONED_HM);
>  	blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
> @@ -129,7 +122,7 @@ static void *nvme_zns_alloc_report_buffer(struct nvme_ns *ns,
>  				   sizeof(struct nvme_zone_descriptor);
>  
>  	nr_zones = min_t(unsigned int, nr_zones,
> -			 get_capacity(ns->disk) >> ilog2(ns->zsze));
> +			 div64_u64(get_capacity(ns->disk), ns->zsze));
>  
>  	bufsize = sizeof(struct nvme_zone_report) +
>  		nr_zones * sizeof(struct nvme_zone_descriptor);
> @@ -197,7 +190,7 @@ int nvme_ns_report_zones(struct nvme_ns *ns, sector_t sector,
>  	c.zmr.zrasf = NVME_ZRASF_ZONE_REPORT_ALL;
>  	c.zmr.pr = NVME_REPORT_ZONE_PARTIAL;
>  
> -	sector &= ~(ns->zsze - 1);
> +	sector = rounddown(sector, ns->zsze);
>  	while (zone_idx < nr_zones && sector < get_capacity(ns->disk)) {
>  		memset(report, 0, buflen);
>  
> -- 
> 2.25.1
>


Looks good.

Reviewed by: Adam Manzanares <a.manzanares at samsung.com>