Re: [PATCH v1 2/2] ACPI: NFIT: Use modern scope based rollback

[Dave Jiang]

On 9/26/23 11:45, Michal Wilczynski wrote:
> Change rollback in acpi_nfit_init_interleave_set() to use modern scope
> based attribute __free(). This is similar to C++ RAII and is a preferred
> way for handling local memory allocations.
> 
> Suggested-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> Suggested-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> Signed-off-by: Michal Wilczynski <michal.wilczynski@xxxxxxxxx>

Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> ---
>  drivers/acpi/nfit/core.c | 32 ++++++++++----------------------
>  1 file changed, 10 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
> index 78f0f855c4de..079bd663495f 100644
> --- a/drivers/acpi/nfit/core.c
> +++ b/drivers/acpi/nfit/core.c
> @@ -2257,29 +2257,23 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
>  		struct nd_region_desc *ndr_desc,
>  		struct acpi_nfit_system_address *spa)
>  {
> +	u16 nr = ndr_desc->num_mappings;
> +	struct nfit_set_info2 *info2 __free(kfree) =
> +		kcalloc(nr, sizeof(*info2), GFP_KERNEL);
> +	struct nfit_set_info *info __free(kfree) =
> +		kcalloc(nr, sizeof(*info), GFP_KERNEL);
>  	struct device *dev = acpi_desc->dev;
>  	struct nd_interleave_set *nd_set;
> -	u16 nr = ndr_desc->num_mappings;
> -	struct nfit_set_info2 *info2;
> -	struct nfit_set_info *info;
> -	int err = 0;
>  	int i;
>  
> +	if (!info || !info2)
> +		return -ENOMEM;
> +
>  	nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL);
>  	if (!nd_set)
>  		return -ENOMEM;
>  	import_guid(&nd_set->type_guid, spa->range_guid);
>  
> -	info = kcalloc(nr, sizeof(*info), GFP_KERNEL);
> -	if (!info)
> -		return -ENOMEM;
> -
> -	info2 = kcalloc(nr, sizeof(*info2), GFP_KERNEL);
> -	if (!info2) {
> -		err = -ENOMEM;
> -		goto free_info;
> -	}
> -
>  	for (i = 0; i < nr; i++) {
>  		struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
>  		struct nvdimm *nvdimm = mapping->nvdimm;
> @@ -2292,8 +2286,7 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
>  
>  		if (!memdev || !nfit_mem->dcr) {
>  			dev_err(dev, "%s: failed to find DCR\n", __func__);
> -			err = -ENODEV;
> -			goto free_info2;
> +			return -ENODEV;
>  		}
>  
>  		map->region_offset = memdev->region_offset;
> @@ -2342,12 +2335,7 @@ static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc,
>  
>  	ndr_desc->nd_set = nd_set;
>  
> -free_info2:
> -	kfree(info2);
> -free_info:
> -	kfree(info);
> -
> -	return err;
> +	return 0;
>  }
>  
>  static int ars_get_cap(struct acpi_nfit_desc *acpi_desc,