Re: [PATCH v14 21/22] cxl: add function for obtaining region range

[Alejandro Lucero Palau <alucerop@amd.com>]

On 5/8/25 02:24, Alison Schofield wrote:
> On Thu, Apr 17, 2025 at 10:29:24PM +0100, alejandro.lucero-palau@amd.com wrote:
>> From: Alejandro Lucero <alucerop@amd.com>
>>
>> A CXL region struct contains the physical address to work with.
>>
>> Add a function for getting the cxl region range to be used for mapping
>> such memory range.
> Worth adding that it is being exported for use by a Type 2 driver.


Sure. I'll do so.

Thanks


>
>> Signed-off-by: Alejandro Lucero <alucerop@amd.com>
>> Reviewed-by: Zhi Wang <zhiw@nvidia.com>
>> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
>> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
>> ---
>>   drivers/cxl/core/region.c | 15 +++++++++++++++
>>   include/cxl/cxl.h         |  2 ++
>>   2 files changed, 17 insertions(+)
>>
>> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
>> index cec168a26efb..253ec4e384a6 100644
>> --- a/drivers/cxl/core/region.c
>> +++ b/drivers/cxl/core/region.c
>> @@ -2717,6 +2717,21 @@ static struct cxl_region *devm_cxl_add_region(struct cxl_root_decoder *cxlrd,
>>   	return ERR_PTR(rc);
>>   }
>>   
>> +int cxl_get_region_range(struct cxl_region *region, struct range *range)
>> +{
>> +	if (WARN_ON_ONCE(!region))
>> +		return -ENODEV;
>> +
>> +	if (!region->params.res)
>> +		return -ENOSPC;
>> +
>> +	range->start = region->params.res->start;
>> +	range->end = region->params.res->end;
>> +
>> +	return 0;
>> +}
>> +EXPORT_SYMBOL_NS_GPL(cxl_get_region_range, "CXL");
>> +
>>   static ssize_t __create_region_show(struct cxl_root_decoder *cxlrd, char *buf)
>>   {
>>   	return sysfs_emit(buf, "region%u\n", atomic_read(&cxlrd->region_id));
>> diff --git a/include/cxl/cxl.h b/include/cxl/cxl.h
>> index 5d30d775966b..2adc21e8ad44 100644
>> --- a/include/cxl/cxl.h
>> +++ b/include/cxl/cxl.h
>> @@ -271,4 +271,6 @@ struct cxl_region *cxl_create_region(struct cxl_root_decoder *cxlrd,
>>   				     bool no_dax);
>>   
>>   int cxl_accel_region_detach(struct cxl_endpoint_decoder *cxled);
>> +struct range;
>> +int cxl_get_region_range(struct cxl_region *region, struct range *range);
>>   #endif /* __CXL_CXL_H__ */
>> -- 
>> 2.34.1
>>
>>