Re: [PATCH 21/26] dax/region: Prevent range mapping allocation on sparse regions

Dave Jiang
2024-04-01T17:07:49Z

On 3/24/24 4:18 PM, Ira Weiny wrote:
> Sparse regions are not fully populated with memory and this complicates
> range mapping of dax devices on those regions. There is no use case for
> range mapping on sparse regions.
>
> Avoid the complication by prevent range mapping of dax devices on sparse
> regions.
>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>

> ---
> drivers/dax/bus.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
> index bab19fc578d0..56dddaceeccb 100644
> --- a/drivers/dax/bus.c
> +++ b/drivers/dax/bus.c
> @@ -1452,6 +1452,8 @@ static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n)
> return 0;
> if (a == &dev_attr_mapping.attr && is_static(dax_region))
> return 0;
> + if (a == &dev_attr_mapping.attr && is_sparse(dax_region))
> + return 0;
> if ((a == &dev_attr_align.attr ||
> a == &dev_attr_size.attr) && is_static(dax_region))
> return 0444;
>